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Questions asked

we are building a new property on slopping Ground, can a basement be still called a basement if 3 sides are below ground level and one side as patio doors that open on to a patio at lower ground level, into the garden.

We moved into a victorian basement flat conversion about two years ago. The sound insulation between us and the flat above is pretty terrible. The landlord above has now fitted a proper carpet and acoustic underlay which has helped the problem but there is still a lot of impact and airbourne noise between us and the ground floor flat.

We have contacted some soundproofing companies to see if we can do anything via our ceilings. Unfortunately the only effective solutions all involve lowering the ceiling height. Our ceilings are already quite low but, apart from the noise, we love the place and do not want to move.

To give us more ceiling height, I was wondering if it is viable to lower the floor in a basement that has already been converted into a flat and, if so, who would be the best people to get a quote from? Is this something a good builder could do and what would be the approximate costs? Would we need a survey / planning permission for this? Even if we could lower it by 3-6 inches that would make a big difference for us.

I live in a victorian terraced house in east london which backs onto a railway line. I would like to know the planning laws for putting a large brick built shed with basement at the rear of the garden, which would be unconnected to the main house. thanks

Hello,

we have bought an Edwardian Terraced house in Leeds which has some damp in the basement. The solid brink walls are made of engineered bricks. From the outset it seems that moisture is coming from the front walls and there is also raising damp. Between 50 cm and 100 cm from the floor are some marks of salt.

The cause has not yet been investigated.

My initial thought was to improve the external drainage in the front of the property in order to reduce the risk of raising damp and protect the outside walls.

We have contacted some damp-proof specialists who have visited the property.

All have recommended straight away that we should purchase the membrane system they provide and install. First estimates are around £25k - £35k. The extension of the basement is about 5 meter by 9 meter and 2.5 meter height.

Now I got two questions:

1. Are these contractors reliable to propose the membrane systems without having a closer look into the cause and extend of moisture and salt in the walls?

2. Are the cost information provide for damp-proofing a basement dated from January 2008 still more or less valid plus some percent of inflation?

3. What do you recomment how to proceed to find the right system for our situation?

Many thanks for your kind information!

We live in a Georgian property and want to use the cellar (2.5m x 3m approx) for storage.  At the moment it does not smell damp but as is typical, the brick floor and walls feel damp.  There is a ventilation brick at ground level at the front of the cellar which lets water in during heavy rain.  There are is no other ventilation.

The electric and gas meters are in the cellar and there is also a light down there.

We are thinking of putting a membrane down on the floor and then tiling.  We are not sure what to do about the walls - perhaps just paint them - although there is the problem that the ventilation brick will let in water occasionally.

We would appreciate any advice as to what we should do to make the cellar dry enough to store tools, camping equipment and household items such as suitcases.  Of course we do not want to spend too much since it will be used solely for storage.

I intend to build a watertight cellar (basement). The company who will build the basement proposes for the walls EK-fiber or steel reinforcement 2x(150X8). The walls will be 390 mm thick and 2,4 m high. The floor reinforcement is also 2x(150x8) and 300 mm thick. The floor is a 13m x 13m. The water table is at -800 mm, but can be flooded at some periods of heavy rainfall. Is EK-fiber a good solution or should steel reinforcement be the preferred solution? Is EK-fiber not better for strength & watertightness? Is there a table or standard which gives guidelines for the dimensions of reinforcement to resist to the pressure caused by the watertable?

We are looking into building a 4 bedroom basement under our patio, as we live within the green belt this is our only choice remaining for extending the house. 

Due to the size of the basement we are considering the costs are becoming alarmingly high (tripple what it cost us to build the house in the first place) and I would like some indepentant advice to a few basic questions.

*   For how many years should a new basement remain watertight ? and what happens at the point when the dampproofing fails?

*   Is there any form of annual or bi-annual servicing that can be carried out on the damp proofing in order to head off problems?

*   I understand that a sump pump should be serviced at least once a year, but what is the life expectancey of the pump? i.e. how often do they need to be replaced?

My main concern, in part due to lack of knowledge and the large sum of money involved, is that  it is possible to build a basement that will outsee our life time and not cause our children problems when time comes to sell the house.

We have two new houses going up in London; smaller two-up / two-down, terraced, finished lofts (storage, not loft conversions) and approved planning permission for full basements.

We had intended to simply use the basements for storage, however, after reviewing your website, we are considering converting to living space.

Two (2) questions:

1.  If we leave the basements as storage areas, do we have to install fire egress / windows and window wells, or just fire-proof the stairwell?  If we convert the basements to living space does each room have to have emergency fire egress, or just living areas?  Minimum size of fire egress?  Any other options on fire egress -- living or storage -- as these are very small plots?

2. Basements are a monolithic concrete pour with the the concrete stem wall extending to the level of the DPC (150mm above finish grade).  I am used to the 3-stage exterior (positive) sealer systems (North American Standard); siliconate penatrating sealer, mastic/bitumin surface sealer, resin board to protect during backfill (and a French Drain system as well).  I have found it difficult to acquire these products in the UK.  Do you know where I can acquire these products?  Not negitive side drainage.

I am writing to see if you can please advise me on a particular matter.

I have a terraced property in Leeds, and the basement and attic have been converted into living spaces.  However, i bought the property as a repossession and subsequently do not have any paperwork that corresponds with this work.  In addition, Leeds City Council have no record of the work being done within their planning department.  I am planning to put a new bathroom (from scratch) into one of the rooms in the basement and therefore thought it might be worthwhile contacting someone like yourself to check that the basement falls within building regulations before i spent money putting a bathroom in.

If you could please advise me of what would be the best way for me to proceed from here i would be grateful.

I look forward to hearing from you.

I am considering a basement conversion. At the front of the building there is no light/window access except perhaps an old coal shute that has been concreted over with just a blocked up pipe sticking out which must be for ventilation. This is at street level. Could I get planning permission to dig down at the front of the building to put in windows? Other buildings in the street have fully separate access to basement flats in this space between the street and the front of the building.

I have a basement bathroom that was converted 16 years ago. In the last 12 months this has begun to leak at the entrance to the bathroom at the joint between the floor and the wall. This is steadily becoming worse occuring more frequently and with a greater volume of water (currently about 1" of water in a 4' by 4' area).

To remedy properly does this mean ripping out the entire bathroom and retanking or are there other methods to correct? I have been advise that installing a draining system down the side of the affected wall (there are no bathroom fittings on this side) such as Type C watwerproofing in combination with a sump pump  may be a possible remedial fix. Is this likely to solve the issue 100%?

I have a cold storage build under my cement porch of our  bungalow...I would like to make a outside entrance because I am not using the cold storage and plus the entrance doorway is already build in so we wouldn't have to worry about the foundation.. How deep should we dig to make room for the exterior stairs and do we need to heat the room because we are heating the house with oil..

Thank you

Norma

I am hoping to sell my terraced 4 storey victorian terraced house. The cellar was converted into a seperate 1 bed flat in1998.A survey has detected damp in several areas.The rooms were tanked out in 1998 and had a 10 year guarantee. When we bought the house in 2006 we had several areas 're - tanked' under the guarantee. Any cost effective solutions to my problem ?

I`m having the cellar converted in my Victorian terrace and finally decided to have the floor dropped down to improve the cellar head-height, it was originally about 6.3ft and have been told by the compnay doing it, that I could get another foot which would give me a much higher ceiling! So, I got some labourers in and over the space of a week they have dug out the cellar (it was loosely supervised) but I have now found that they have gone well below the footings!!! I`ve done some research and found that unless this is underpinned its risky, the company have now turned around and said that I have dug too low but they can easily remedy the situation for me, by putting in more concrete and more hardcore base for the floor which would give me a floor of at least 8 inches. Where the walls are still exposed below the footings (Which wouldn`t be by much once the new floor is in) they are going to put a concrete shutter around the perimeter of the room and where needed steel bars to give the correct integrity back to the cellar area below the footings.

I`d like to know from an independent source, if this is a viable solution to safeguard the integrity of the cellar and also to meet building regulations. How good is this idea, as I`m still able to determine the way they progress to a degree. 

I`ve also read about "Party Wall" something I`ve never heard about before and this has not been mentioned by them to me before etc which I find worrying, also they have never sent an independent engineer to assess the situation.

I`m now quite worried as I don`t want to have a conversion which could lack integrity and also affect my neighbours properties as well.

Hopefully somebody can give me some advice.

I own a ground floor flat (freehold)in a converted house built around 1900. There are 5 other flats in the buiding, including 1 other ground floor one.

There is a unused basement under my flat that I'd like to convert to a music room. It is seperate from the basement (if one exists) of  the neighbouring ground floor flat in the building. It can currently only be accessed through a hole in the floor of the shared understairs cupboard in the communal hallway. However, there is a staircase under my hall leading up to my flat from the basement that was at some stage blocked off.

Can you tell me if I have rights to the ownership of the basement or are they shared with the other freeholders?

Also, there are a few non-load bearing walls (that divide the basement into 3 samll rooms) I'd like to remove. Are there theoretically any issues with doing this?

Thanks

We are considering buying a four storey house with firends. They would have ownership of the top three floors whilst we would have the basement self contained flat. The house and flat are for sale as a whole at the moment. What is the best way to purchase and what are the  implications for freehold/leasehold please? Is it better for someone to buy the whole thing and then sell the basement on or shall we try and get the owner to sell separately/ Thanks! JH

Are you aware of any occasions when permission for a basement has been turned down by the planners because the resultant replacement dwelling would be 'materially larger' than the existing. 

This would involve the planners including the floorspace in the Basement within their calculation comparison of the before and after.

As such it would according to the planners be unacceptable in the Green Belt in relation to Planning and Policy Guidance 2 (PPG 2) clause 3.6.

On a related point I note from The Daily Telegraph of 13 March2010 under a "cinema and media rooms" heading that  "buyers are refusing to include basements in the square footage of a building".  any comments?

I have a large celler comprising of a number of rooms one of which contains an AGA and 2 Aga fridge/freezer.  I would like to start planning a basement renovation.  One task is to raise the height of the rooms - which entails digging out the floor.  To remove the AGA and  fridges out of the cellars would be a massive task.  Would it be possible to reduce the height of the rooms one at a time so that the aga can be temporarily moved into another basement room?       

I work for a charity-based housing association (www.canopyhousingproject.org) in Leeds. Our portfolio is mostly comprised of Victorian back-to-back terrace housing, with damp issues and flooding cellars being a common theme! We are not intending to convert our basements at the moment - to start with, we would like to be able to keep them dry and rot-free!

We currently have a problem with a house that can have a flooded cellar during heavy rains from where the pavement, with a cemented over 'coal' hole, meets its outside wall (there is no garden). Added to this, there is a lack of ventilation in the cellar, probably due to its ceiling being below street level - no air bricks have been fitted and would not have met the 'outside' even if they had have been. Would anyone be able to suggest a product or method to rectify this? A telescopic venting system perhaps? Although that would probably mean using space in the floor above...

Any advice would be very much appreciated.

How far can i dig down is it to the last brick

I have a space under my house which is about 5 foot and I am looking to make it into a basement can you please tell me on digging a test pit how far can I go down before I have to underpin

Have you any suggestions as to how we can cross vent ?

many thanks in anticipation

Duncan Foster

What is the latest on permitted development rights for basements? Sevenoaks DC has just refused us permision for a fully submerged basement as an additon to an existing permission. No change to the above ground structure, bulk, etc. This issue ned to be moved on. What can be done to put more pressure on central govenernment? Can we help?

You commneted "The new GPDO which came into force on 1 Oct 2008 does not specifically include for basments. There is a separate Order being discussed for basements and we will advise on our News section as and when (if) this is issued.

Planning consultation has taken place and interestingly some planning Authorities included basements within the old Order, even though they were not sprecifically. So possible that some may include basments within the new GPDO  (But not specifically listed). However, that may not happen in view of the pending order specfic to basements". 

We live in a ground floor conversion flat with a basement accessible only from inside the flat. The building has 5 flats owned by leaseholders. The basement is about 26 square meters and we're thinking of convert it into a studio flat with an independent entrance. To do this we will have to knock down 2 walls and replace them with beams and pillars. May you give us an overview of what is involved? Regulations, mortgage implications, structural issues? Many thanks.

we live in and are leaseholders of the raised ground and basement floors of a four storey victorian house with 20m garden. We have sole access to the garden, both via the basement and via a terrace with steps we constructed at the rear raised ground floor level with its own steps to the garden. We also own the first floor flat which we currently rent out.  We now may have the opportunity to buy the top floor flat - but we would seriously strugggle to afford it.  So we were thinking of buying the top floor flat, making our dwelling the raised ground, 1st and top floors - thereby getting the benefit of the beautiful spacious stairway and common parts and creating a better laid out 3 storey home.  If we did this we would need balance our income by converting the basement from its current use - our bedrooms and bathrooms - into a 2-bed flat with its own separate front entrance, and either renting it or selling it.  So i have a number of questions:

How and what level of sound insulation would I need to install and could this be on the ceiling of the basement flat? (we have just laid a new floor thoughtout the raised ground floor.)

Would it be reasonably straightforward to convert the basement into a separate dwelling? (It used to have a kitchen , 2 beds and bath when we first bought it).

If I have tenants in the self-contained basement do I have to offer them any use of the garden (they would have a door to the garden)?

 Any advice gratefully received

we would like to convert our celler into a kitchen but the height is only 1.8m .can this still be done  or is there a minimum height that we have to comply to.

Do you have the names and contact details of any prefabricated basement LIGHT WELL manufacturers or suppliers available in the U.K.

Thank you.

Our house is on three levels, the basement was already converted when we bought the house. It is now a dining room and kitchen, the wall to the dining room ends at the begining of our lounge on the next floor up and I want to knock the wall down to extend the room to the full length of the house.

Do I need planning permission? Do I need building permission?

Many thanks

Jay

I am in the process of buying a Victorian terraced house that has a 13.5m2 cellar already converted. However, the headroom is only 1.90m, and I would like at least 2.10m. Is cost of doing this less than a new conversion which I understand to be ~£2000/m2?

Hi, we are building a basement extension to our house and want to build it as insulated as possible but the more I read about insulating basements more confused I become!  There seems to be completly opposite views regarding whether the ground is a good insulator or not and whether its worth increasing insulation levels. I don't understand why floor insulation makes a such difference if the ground is such a good insulator?

I am currently an Undergraduate Student studying at University Level. I have been given the following brief by my senior lecturer, and within it told to contact relevant construction companies offering the services mentioned, in order to conduct my research.The brief is as follows:

A petrol station situated on the parkway (main road into Manchester city centre) is to be demolished and replaced with a six storey office block. The office block will contain a basement which will include a canteen with kitchen facilities and a staff common room.

The ground conditions consist of existing pavement construction of sets laid on 65mm of grit sand and 600mm of hardcore. The sub-soil below the hardcore is mainly filled land containing old brick rubble approximately 1000mm deep below which there is clay to a depth of 4000mm followed by a bed of gravel at least 6000mm deep. The water table is 900mm below the ground level. The petrol station is situated between two existing commercial buildings which are a distance of 3500mm from the boundary of the petrol station.

Within your research you must analyse the option of providing a basement in the proposed office block, therefore considering issues to do with the site and basement proposal is neccesary. It is vital to contact relevant companies that offer basement construction and waterproofing as part of there services, as there response will form your research.

Therby, I would like to give you the oppurtunity in providing me with any responses you might have to the questions relevant to the brief which I have listed below:

1) What issues in terms of the site and the proposal for the basement should be considered before the petrol pump is demolished and replaced with an office block (inc basement). ?

2) What would you suggest as being a suitable type of construction (excavation) method for the proposed basement in the multi-storey office block?

3) which of the materials in the current ground conditions would you reccomend as being most suitable to build the basement on. Bearing in mind the depth of the basement is to be 5m from ground level to basement foundation level.

4) As the water table is at a height of 900mm, what are in your opinion any issues this may cause in the proposed basements construction.

5) Finally and most importantly, what type of waterproofing system do you reccomend be used for the proposed basement given the current site situation.

I hope you can offer me the responses i need in order to conduct my research into basement construction. 

I am considering digging out only the centre of my basement to avoid underpinning the walls. Is there a particular term for this type of work? I'd ike to do some research but don't really know what I'm looking for and all I can find are underpinning articles.

 Presumably even if I proceed with this method I would still need to involve a structural engineer, party wall surveyors and building control?

I have a detatched house with an existing 100sqft basement, built around 1932. At some point the space was cleared and concrete laid with some areas having polythene put under it. At present there is about 2.5m height, a timber staircase and a rear exit and one window. The back wall and part of one side of the basement are at ground level the other two and a half sides  are 2.5m below ground. We are well above the water table and the ground was originally part of a gravel quarry, the main sewers are some 3m below the basement ground floor level. There is clear evidence of effloressence and degredation of the blockwork. When there is heavy rain the front wall allows enough water penetration to have standing water but this could be controlled by better outside drainage.

We have planning consent for an extension and basement conversion but would like advice on the best methods for stabilisation of the blockwork and for waterproofing the rest. We would be intending to put in light wells in the perimeter and the open rear wall will have french doors fitted. We have already had structural steelwork installed on concrete pads to a structural engineers designs to allow us to have one open space under the house, which is what was there before but is now structurally sound.

If you could suggest any construction experts in our area that would help as well.

I would like to know if/what the council could do about a basement that was converted into a flat four years ago,without planning/building consent?  the flat is self contained, has its own entrance, although shares utilities/heating with the main house.  has been rented out for the past few years. 

 my cousin would like to sell this property but does not know about the best way forward.

I have a terraced property that currently has a single basement flat that has its own independent entrance.  I would like to refurbish this space and make it an open plan self contained stuid flat.  My question is that as the space from the front door to the back of the flat is less than 9m (7.5m x 4.5 m) am I required to create another exit for use in emergency or will the main entrance suffice?

Many thanks for your guidance.

I have been showed a 2 bed terrace with a basement that has been converted into 1 bedroom, i1kitchen, 1 bathroom & 1 lounge. The conversion is up to a high standard but has been carried out without planning permission & building regulations approval. furthermore there is only ! door ie. the main exit which is a separate door leading to stairs at the front of the house. however there is no fire exit.

is there any way I can buy this house & rent out the basement as a flat?

Thanks

We live in a very old thatched cottage (circa 1750/1800).  Many of the properties in the village are of a similar age and style, and many have cellars.

We have heard from someone local that he beleives our house had a cellar at some stage as he used to play in it when he was young; he is now in his 50's.

Is there an easy way of finding out if there is indeed a cellar without breaking open the floor?

We have a Victorian mid terrace house built around 1900 which has a cellar.  We didn't think we needed any permission to spruce up the old cellar.  In doing so, we took the existing floor out which consisted of stones and rubble, we took the floor down about 6 inches and then layed 4 inches of concrete in it's place.  this has given us about 2 inches in head height.  I have just had a conversation with a friend who thinks we may have needed to get building regs involved and after doing research on the web anm now worried that we could have problems with underpinning and party wall issues.  Do you know if this is the case.  I am very worried about it.

We have full planning approved for a large individual self build dwelling and are currently in the middle of submitting our application for Building Regulations approval. Our builder & architect have muted the possibility of incorporating a basement as part of the foundtion plan but planners are telling us it would require a full submission instead of a minor amendment to plans (even though there are no windows or material changes to the appearance of the property). Is this normal practice? Are there any planning guidlines on adding basements? Are there any similar cases you can advise us of?

I have a terraced house (middle of three) with a full basement,a front "garden" of at least six foot,with a further nine foot pavement to the road.I would like outside access to the basement from the front of the property. I have seen properties elsewhere that have this.Could you tell me what would be involved in doing this, and the best /safest way of doing it.

I recently bought an Edwardian House which was previously poorly maintained. I would like to restore it as much as prcatically possible. I think there may have been a basement/cellar here which has since been filled in. There is a strange waist-high widnow on the side of the pantry (as though the pantry originally had steps down to a cellar). Also, there is a large conctrete area outside the pantry (below the window) as though there may have previously been access to a cellar/basement. I can post pics if you think you could help. I'd love to restore th basement. Regards Mark

Is there a way to use the underground nature of a basement wall to factor into a standard wall U-value calculation to give a better u-value result to a basement wall?

Thanks a lot

Alex

Can you tell me what year basements stopped being built when a house was being constructed. If two semi's are built in exactley the same way , would only one of them have a cellar. Do they always have an air vent above the ground.  My neighbour claims he has a basement I do not have one both houses are identical, constructed about 1935  there is no evedence in my house of there ever been a basement.

I’m currently completing ‘U’ value calcs for a basement construction and wondered if you may be able to provide an example please, so I can make sure I’m getting the correct result. 

The wall I’m trying to model consists of unbridged layers of  - plasterboard, 100mm 7N conc blocks, 100mm mineral wool batts, 100mm reinforced concrete. 

As I understand that the basement floor, when insulated can affect the wall 'U' value, the floor consists of 65mm screed,35mm extruded p/s ufh matrix, 40mm Anhydrite liquid screed, 50mm PIR insulation & 300mm r/c

Ave depth of basement is 2.5m, and the perimeter/area ratio is 0.5498.

We are in a terraced Georgian property, which was originally all part of the same house but we believe we have more of the Servants rooms.  The two grander parts of the originally linked house on either side of us(now separate residences),  have large usable basements/cellars with staircases.  We don't have any evidence of a cellar but were told there may have been one that was filled in.

We would really like to find out if there was a cellar but don't know who to ask to start looking or what to look for. Is there any typical locations for entrances to cellars eg, under the stairs, front of the house???

Is there any piece of equipment we could hire which would indicate a void??

Any help or advice at all woudl be gratefully received.

We live in a ground floor flat of a victorian terrace and use the cellar as storage space.  Typically the base used to get damp/wet after heavy rain, although recently (with no rain), we have had up to 15mm of water.  

Just before we noticed this water depth in our cellar, our neighbour had had their cellar tanked (cementitous render with water-resistant additive by the look of what was being mixed outside).  When we approached the tennants next door to see if they also had water problems they confirmed the tanking was due to up to a foot of water in their cellar, which had arisen after the terrace the other side of them had also had their cellar tanked.

I am trying to understand whether i should be concerned.  We do not have a leak, therefore presume it can only be ingress of groundwater (in absence of rain), but can't believe the adjacent cellar would change the ground water pressure applied to our cellar?   I suppose it may help if i can identify the level of their basement relative to ours to see if this could get worse!?

If it is possible that the tanking to the cellar next door has caused water to flow into our cellar instead (and potentially rendering it un-usable), do we have grounds for legal action since no party wall agreement was sought for their works?  I appreciate that there has been no structural change, but their activity has potentially resulted in change of use our side (presumably similar grounds to installing a window overlooking property etc?).

To resolve the issue of water in the cellar in the immediate future - essentially to keep the floor dry, i am intending on installing a light duty clean water sump pump into a sump in one corner.  The cellar is about 7m x2.5m on plan, and i was wondering how deep the sump would need to be to draw water away from all areas of the floor? (ie leaving no wet patches)

Sorry for the length - Any help much appreciated!

I live in ac property which is one of six in a converted manor house. There are five properties above ground and a sixth which is the basement flat.

We have just discovered a pump below the basement flat which pumps surface drain water , not sewage which is dealt with by another pump.

The electricity supply to this pump is situated within the basement flat.

 We are now trying to ascertain the responsibility of this pump. Would it be usual for the responsibility to lie with the basement flat or to be shared by all six flats.

The six flats share the freehold of the property. Theres is nothing in my lease referencing this pump.

 Would really appreciate some advice.

Do basements constructed to type A form of construction and waterproofed externally using a bonded sheet membrane (protected, backfilled and maintainable  land drain in place) comply with BS 8102-1990 even though they cannot be repaired if defects are present or occur and ground water enters the building(assuming grade 3 env).

Just converting my cellar into an office cum den.

Re the original concrete stairs leading down to the cellar from the living room - just wondering (bearing in mind its a low cost exercise)

a) timber the stairs a put on a carpet

b) leave the original stairs & maybe apply a conrete treatment/gloss etc. to smarten them up?

I was thinking the latter, but wondeed the best way to go about it?

Hello, we live in a 3 bedroomed mid terraced property and the missus wants a single storey utility room at the back of the house to include our washing machine and dryer and our fridge freezer with some space for the ironing, i believe we are allowed 50 square feet by our local council before planning permission would be needed. i thought possibly 8ft by 6ft or a better configuration, my question is how deep would the foundations need to be and what requirements are there for windows, any advice is most welcome.

I theorectically need to remove a mid terrace house with basement, retain the facade and then construct a new 3 storey house with basement on the site.

I was hoping to use a prefabricated basement system with the walls performing as foundations also.

Is this possible? and what would be the name for this process please?

I am in the process of designing a dwelling that will include a part basement (approx 25m2, for use as a garage). My concern is how I will join the basement foundation to the rest of the building substructure. Obviously I could step the footing, however this will be difficult to implement on our particular site ( my understanding is that for each 450mm step I will need an overlap of 900mm. Therefore if we take me a run of 4.8mtrs to step 2.4mtrs). I read this on an american site:

It's pretty common for a short wall to tie into a tall wall, especially in the North, where most houses have full basements but garages just have short frost walls. The code calls for continuous footings at all points. But that part of the code dates from the days when foundations were made mostly with concrete block, not poured concrete. Masonry foundation walls have no real spanning capability, so they have to be stepped down when elevations change.

Concrete walls, on the other hand, can be reinforced with steel to span openings. That means the footings can be discontinuous, jumping from the 4-foot to the 8-foot or 9-foot elevation. The shorter wall can span the distance.

The concrete has to be appropriately reinforced. A typical house situation, where a 4-foot garage frost wall has to span 4 feet or less and tie into the main foundation, calls for two #4 bars at the top of the wall and two #4 bars at the bottom. The steel has to extend 3 feet into the main wall and 3 feet into the shorter wall beyond the point where the footing starts.

For this detail, the footings are formed and cast as usual. When you form the walls, the bottom of the forms must be capped with a piece of wood where the forms pass over empty space. In termite country, that wood must be stripped when the forms come off.

Unfortunately the illustrations from the page would not transfer into this window so here is the url:

http://www.concretenetwork.com/concrete/footing_fundamentals/changes_in_elevation.htm

However, I can find no information regarding the use of discontinous footings in basements in the UK (either on the web, in Part A or Basements for Dwellings). I suppose in essence a piled foundation is nothing more than a series of discontinous footings so I can't believe they would not be allowed however the lack of any guidance on their use leads me to believe that they may be unacceptable.

Any suggestions?

I would like to fill a cellar beneath a terraced victorian house.  It is approximately 4m x 5m in plan.  Assuming that gas and electicity meters will need moving and that the fill material can be poured in via reopening the coal shute, could you give me an idea how best to go about this and also the approximate costs to:

1.  Fill it completely e.g. a height of about 2m.

2.  Partially fill it e.g. a height of about 1m.

Thank you.

Under the new GPDO 2008 do dwelling house basements need planning permission?

We are planning to build a new bungalow with a full basement that will include a living room, an office, a prayer room, 2 bedrooms, a gym, a wet room, and a store.

Do we have to provide direct light source and ventilation like windows in the basement?

We have spoken to an eco consultant engineer, who said he can provide a cooling/heating aircon system that will provide 24hours fresh air all over the house, and the basement will be lit properly. 

I own the ground floor flat of a victorian conversion and would like to add some basement living space. I own a share of the freehold with the 2 flats above me and am based in a conservation area. Firstly, do I need planning permission? Secondly, do I need approval from the other freeholders before embarking on this project? Your feedback would be gratefully received.

We have a 200 year old cottage with a number of cellars which open to the garden at the rear of the property the land slopes from front to back so the front of the basements are below ground level. We are having new draiange put around the house and would like to take the opportunity to waterproof the basement wall at the front (ie below ground level) the foundations are stone and the basement is aprox 5 - 7 feet below ground at the front. Please advise what I should put on the outside of the stone foundations to reduce/stop ingress of water.

We are hoping to fully convert the cellars at a later date.

We had our basement converted aproximately 4 years ago and the builder  informed us that we did not need Planning Permission,at the outset.He also assured us that all the work would adhere to Building Regulations,but it was never passed by the Local Authority,prior to,during or at the end of the job.
I am aware that that this will cause problems when we come to sell the property and although i know retrospective Planning Permission can be obtained,i don't know if this also applies to Building Regulations?
I also need to know what this will entail and if it will demand that the all the finished work be removed,in order to inspect thoroughly,as this will no doubt prove costly?
The builder used the Newton's membrane & pump system and we have had no problems with the waterproofing aspect of the work,but there is no insulation or sound proofing under the plasterboard ceiling and the floor above is suspended wooden floorboards.The Saniflow system was also incorrectly installed and is in effect,useless.

I would therefore be grateful if you could advise us how best to deal with these issues,in accordance with current regulations.We cannot approach the original builder,as we parted on very bad terms,so should we approach a specialist company to rectify the problems the first instance or contact a surveyor?

Thankyou.

We have a two roomed basement as part of an extension to our house that was completed about 4 years ago.  The basement was tanked externally using Proofex 3000 on the walls and Proofex Engage in the floor slab.  The site is very near the top of a hill but has steep sloping banks at the rear rising to about 8 metres above damp proof course level. No perimeter land drain was installed by the contractor who relieved the architect of supervision responsibilty and even changed the waterproofing system design from internal to an external system.

Earlier this year year during a period of continuous heavy rain, water  poured into the basement. The original building contractor and his waterproofing sub contractor eventually after many trial and error attempts found the location of the leak and were able to excavate some 4 plus metres under the existing house and three times attempted to effect a repair by patching and re-inforcing the toe with waterproof concrete. Each time the tanking has continued to leak when tested by filling the excavated hole with water.  They have decided to abandon the external tanking and start agin internally.

It has taken over three months to get this far and it is clear that neither the contractor or his sub-contractor really have a clue what to try next as we are having a number of visits from cementitious material tanking suppliers, from SIKA to polymer type rendered systems, all of which have their own particular difficulties in application to our basement.

Whislt not of course waterproofing experts, we are able to understand the mechanics of what is involved and have even obtained a design and quotation ourselves from a local contractor who whilst also installing cementitious rendered solutions strongly recommended a cavity design membrane system with dual pumps and battery back up in event of failure.  His argument was that as the basement was not built with the benefit of a perimeter land drain and water is now certainly going to get through the reinforced concrete block walls, it is best to accept this as fact and deal with the water by collecting it and pumping it out when needed.

We have passed the quotation on to the building contractor who is meeting his responsibilities in trying to solve and correct the problem but he is absolutely against CDM systems, prefering a cementitious rendered solution.

As the stairs to the basement lead directly without doors from our kitchen/dining room, the disturbance to our daily life is also a major consideration. 

What would be your advice please?

My wife and I live in Birmingham and we are looking to buy a new property to live and work in. I teach drums and and at the moment have a recording studio in another property but would like to move the studio to my home for many obvious reasons. We have been looking at properties and have found a very nice victorian mid terrace with a basement. The basement is 3.76m x 3.30m approx and is located benith the front recption room. My questions are these: Is it possible to extend the basement either going under the front garden as well or further beneath the rear reception? Is it easy to sound proof to a sufficient standard so we don't become the neighbours from hell? and any idea of cost/who I would need to contact?  Any help or advice would greatly be received. Thanks

I am seriously considering purchasing a 1900’s end of terrace property in West London which has a good sized cellar (26' x 11').  The floor height is 5' feet so it will need to be dug down and lightwell/window will need to be put in.  Can you give me a ball park figure as to how how much it would cost to make this into a liveable area?  I am trying to gauge how much I would need to get the job done prior to submitting an offer to purchase the property - but at after a lot of searching I still have no idea of the rough cost involved.  Also, please can you recommend some companies which have successfully completeed such projects.

I've already asked some questions which you have mainly answered (thanks). I'm replacing a floor in a cellar (Victorian Terrace) which will be used for storage only. The current floor is concrete, but is subject to damp.

Please could I ask the following:

What thickness should the new concrete base be (domestic use only)?

Would a self levelling floor screed be better than standard concrete, or should the floor screed be used only after a concrete base has been laid? 

We have planning permission for a new build basement externsion next to our current property, actually its not a true basement as we live on a hill and the front of the extension is level with the road but the rear and sides are below ground level. The site is quite tight for space and we need to build right up to the boundaries so there will not be room on the outside to apply a waterproofing system. I see lots of different options for waterproofing internally and externally. I don't really like the idea of the internal systems. I am wondering if there is a solution where the waterproofing is applied on the inside of the wall in the cavity but not on the inside of the innner skin of the basement. I like the idea of waterproof concrete but am I correct in assuming they still need space on outside of the wall.

My parents are currently  in the process of selling their house.  They have a wood basement, and the realator is telling them that the basement is stopping them from selling their home, because people do not want a wood basement.  they have lived there for 24 years and have never ever had an issue with the basement at all.  Could you please tell me the pros and cons of a wood basement veruse the alternitive?  She feels if she is more informed ( and the realator, who should be) she can help the buyers see the advantages as well.

Hi, I have recently contacted you with a couple of questions regarding the conversion of my cellar and eagerly await your response, however, I now have a couple of other questions to ask.

I would like to install a wet room to my basement as opposed to a shower room. Is this possible? Would I have to install new drainage or can I run the waste into a macerator or indeed the tanking pump?

I'm in the process of replacing a concrete floor in my cellar. I live in a three bedroom Victorian terraced property in Chorlton, Manchester. The cellar will be used for storage only (not a living space) so does not need to be tanked with a damp-proof membrane system. However, I do wish to place a DPC membrane under the floor (visqueen).

Please can you kindly let me know what the construction detail should be for the floor in the cellar?

If I use '20mm to dust' stone, would I need a layer of sand also (on which to lay the visqueen)? How thick should the concrete layer be? Do I need an asphalt layer over the top of the concrete? Is it better to use a pre-mixed floor screed from companies such as Ardvark premixed concrete? Is it recommended to install some insulation under the floor? If so, what should this be? The only extends under half of the house, so is not a large area.

Any advice would be appreciated...

Is there any firm guidence, case law or Planning Appeals on the provision of semi basements, i.e. on a sloping site, and the assesment of the gross floor area allowable for a replacement dwelling? The arguement being that the basement use is non habitable and imperecptable from the outside. Thanks

To what depth is the land beneath your house legaly yours?  im planning on knocking a existing corrugated asbestos garage down and replacing it with a block built workshop with concrete floor basement,size of existing garage is 3.5mx6m the surrounding soil is of free draining consistancy with no flooding issues,would this be an expensive project ? how would this affect other projects ie loft conversion,house exstension in terms of increasing property volume?                                               

I need some advice on penatrating damp in my cellar and the cheapest way to cure it . and can i remove the two thrawls in the cellar.

I have a double, half submerfed concrete air raid shelter in my back garden. I believe that it pre-dates the Second World War. There is a window at one end and steps leading down from the garden to the entrance door at the other.

When I first moved in, I used to store items in the shelter but have not done so for years when foxes appeared to be colonising the same. Now I very much need the storage space but it is currently under 2 + inches of water - rising according to the weather.

May I have some advice as to how best to recover use of the shelter for the future ie to weather-proof it?

Many thanks

Hi all

I have been asked a question about the most common type of wall construction used for basements, with your experience would you say solid brick, backfill, cavity, or reinforced concrete, thanks in advance, Simon

I have a basement with outside ground level starting only about a foot below the basement ceiling level.    I am informed that to satisfy planning/building regulations, this ground level can only reach 2/3rds of the height of any basement window.

This would mean that should I wish to install large windows (with egress), I would be forced to lower the ground level outside to the relevant level against the windows.    I am further informed that for the purpose of considering whether the ground is in fact only 2/3rd up the windows, a lowered ground level would not be permitted.

Can anyone tell me if this information is actually correct as it would seem to rule out anybody actually converting an underground basement into living accomodation (to be rented out) ?

Many thanks

We're interested in getting a retro-fit basement under our semi-detached 1960s house. The biggest problem we can see (apart from the expense!) is the solid concrete floor - how do you get around this problem?

What is a typical cost for a retro-fit basement, 6m x 7m? Is it possible to keep costs down by doing any of the work yourself?

I am having a sun pipe / solatube installed in my basement and I have a concern about keeping moisture out of the home once the pipe passes through an external wall. The pipe will pass through the outside wall of the house (under the bay window) and will finish above the patio. I have been advised that the sunpipe will need heat and moisture insulation by means on passing the sola tube (530 diameter) through a waterproof pipe acting as a shield to moisture.

On the outside of the bay window wall is earth (with a patio on top) and inside the bay window is a void that leads to the stud wall entering the basement room.

As the bay window needs to have bricks removed (and lintel fitted) for pipe to pass through I plan to cement the pipe in place to the brickwork to provide a waterproof barrier for the pipe to pass through. Do you know if this is sufficient and if there are better/other alternatives ( I am a homeowner and not a builder so I am limited on my knowledge and experience)

Regards

Alex Hind

Can you please advise me if there is a system for tanking a new basement with insulation on the outside, the basement walls will be insitu concrete reatining walls, the inside face of the walls are to be exposed concrete so the insulation will be on the outside face of the concrete wall, is there a tanking material (system) available that can be applied  directly onto insulation so that the insulation is kept dry.

thank you

Tadhg McMullen

I live in a 1-bed garden (front and back) flat in Streatham, South London. My flat is ground floor left of a large converted Victorian house. It is leasehold.

I also own a 320 sq feet basement/cellar beneath the building which is only accessible from my flat. This is on the same lease terms as the flat. The problem is the majority of the area runs not under my flat but the nextdoor flat (ground floor right).

My goal is to make the basement a living space. Its area consists of three rooms, essentially. 1 under what is the communal hallway of the house and 2 are under the nextdoor flat (ground floor right) and extend right under. There are old coal shoots in each which would be perfect for light if it did not mean using nextdoor's land for access.

What are my options? Can I just tank/waterproof the space and use it without lightwells and fire escapes?

Additionally, the height of the space is about 7ft throughout. Not too bad but I wonder how complicated it would be to increase this to, say, 8ft?

Thank you.

I live in Dorking and Mole Valley planning area.  My house is in an Area of Outstanding Natural Beauty (AONB). I have 2 acres of land and would like to put a large basement in the garden well away from the house.

Do the planners have a right to object if it is not seen and is hidden underground ?

How big can a basement be?

The cd published with the June HB&D mag. building a basement. Do you have a cd that can be played on a normal cd player