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Questions asked

We have recently formed a small shower room area directly below the tiled concrete paved entrance to the property which is at ground level.

The new shower room is in fact an extension to a previous basement project. The new room is formed of  2 new 250mm thick reinforced concrete walls, whiich have been tied back into existing structure with dowel bars.

We are now at the stage of sealing the walls are are looking for a cost effective solution to ensure watertightness. The room is approx 2.5m x 1.3m in size, so we feel a drained cavity isent best suited as it will encroach on an already tight sized room. The floor and wall areas combined are less then 20m2.

The finish to the walls will be tiles full height. Can you recommend a product that can be applied directly to the concrete and brickwork walls, that can easily fitted and fairly inexpensive. We were thinking something along the lines of a paint system or polythene sheeting that would suffice. 

If you have an idea on potential cost per m2 for such system that would also be helpful. 

An early response would be greatly appreciated.

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!

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 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 live in a property dating back to the 18thcentury.There is an old vaulted cellar below my sitting room which when i discovered it was full of water to a height of about 4feet.It seems the previous owners knew nothing about its existence.There has been a sump pump down there for the twenty years i have lived here and it has caused no problems.I  am now wanting to sell the property and i am concerned that potential buyers may be put off knowing that there is water in the cellar as sometimes the floor can be wet from water seeping from the base of the walls.I w ould like to stop this so the floor looks dry and therefore tidier but i do not know what the best way to do this would be,perhaps to put concrete down to raise the level of the floor?The cellar is about 12ft below the property and will never be used.

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". 

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

Thank you.

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 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.

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).

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?

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. 

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?

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? 

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?

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

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 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

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 ?