Basements with a new build

sas

Hi,

Does anyone have any experience with basements. It's something we're thinking about. Would be pretty cool for a cinema room for example. Also it would be very handy for storage given that we may have to build a dormer and won't have much of an attic.

Just wondering what sort of money you'd be talking about.

Viking House

We have experience with basements, we will be doing two this Summer.
We are building them with 400mm Poroton blocks and will backfill with LWA as extra insulation and to reduce the ground pressure against the wall by 75%.

There is more info about our systems on the website.

foamcutter

It may be worth checking ICF (Insulated concrete forms).

I came across this information on a site polarwall

The primary markets for ICF are:

Private housing
Social and affordable housing
Commercial
Basement and retaining structures

Pataman

At the moment I am building a new house with a basement of 16x10m. The biggest problem is the water table, it is very high in my area. I am going for a raft foundation and ICF(polystyrene type lego block) as shuttered walls in the basement with a timber frame house above. The basement will have to be well tanked to prevent water ingress. It is quite expensive. In the basement alone we dug out 80+ loads of muck.

Breezzzzze

A basement isn't really a DIY option. Reinforced concrete with tanking is usual if the basement is to be used as habitable space, which will add to your house price considerably. Also, if a large open plan basement is what you envisage, a (typically) steel structure will be needed to transfer the loading from the walls to the ground. This too is expensive. An engineer would definately be needed for both the basement structure and the steelwork. I don't mean to be a pessimist, but advice that you get an idea of the cost before you go very far down this route.

Pataman

The structural engineer will cost about 5-7k. It will be a raft foundation, which is a lot more concrete than strip foundations.excavation will cost about 150 - 170 per truck depending on where you are. Then there is the price of the groundworker to fill the trucks. Remember the extra space is well worth it. PM me if you want details.

Viking House

It doesn't have to be a raft foundation if the ground conditions are good.
If you reduce the ground pressure externally and drain well by using LWA then you can build it with blocks.

Cmar-Ireland

I would be interested in finding out more about this. We are hoping to build a house in the near future, and including a basement was something I would love to do. Something about 12 to 15m square.

Ideally I would have my home cinema there and a pool table. I would also like to have the laundry room down there.

What about the hot water cylinder and pump for the taps? Could they be put in a basement? Do you need more than one means of escape in the event of a fire etc?

How much would it cost to add this to a build, based on direct labour for most of the work (engineer aside).

Cheers

nosmokenopoke

Hi,
I am just wondering if you went ahead with the basement and how you got on ??
Start my own project in 4 weeks thanks

Cmar-Ireland wrote: »

I would be interested in finding out more about this. We are hoping to build a house in the near future, and including a basement was something I would love to do. Something about 12 to 15m square.

Ideally I would have my home cinema there and a pool table. I would also like to have the laundry room down there.

What about the hot water cylinder and pump for the taps? Could they be put in a basement? Do you need more than one means of escape in the event of a fire etc?

How much would it cost to add this to a build, based on direct labour for most of the work (engineer aside).

Cheers

North West

Hi sas.
You will need tank the outside of the basement with a waterproof membrane. Google graceconstruction.com. look at the bituthene 3000 + (accessories requied to do the job) below grade products. This product is available in ireland and the company have a Representative on hand that can help you. Check through a building merchant that deal with this company and they can have him call to your builder or developer.
NW

nosmokenopoke

I am also wondering if I'll get away with building the basement up in block oppose to shuttering it as im on a hill and 1 full wall will be fully exposed so you would imagine this would significantly lower the water pressure against the build when back filled around ?