Rear extension query.

[Bouba]

I want to do a rear extension. My garden lever is 1ft higher than my house floor level as, I am on a bit of slope on road.

What do pro's normally do when the rear wall of the extension sits next to soil level. Do they leave a little space with a french drain or set it back a bit with a roof overhang to protect the walls.

What about the bottom of walls. Does it gets rendered and forms a plinth like early 1900 properties.

 

[freddiemercurystwin]

It depends on the site conditions, how much space you have and what is proposed outside, do you need to have a door access out through the wall etc. Sometimes you would build it as a retaining wall, sometimes the ground can be cut and banked, or a path around the house and then a retaining wall to retain the existing bank. It varies.

If it’s built as a retaining wall it would be tanked.

Don’t understand your reference to a roof overhang to protect the walls bit.

 

[Bouba]

Thanks. No door access on that wall. Just a window to see the garden(while i do the dishes and mrs watches tv)😤. There is a retaining wall holding the soil.

My worry is that there will be a little alleway between the retaining wall,and the new extension wall. Wont water collection be an issue in heavy rain. Would incorporating a acco drain be advisable.

What would be a best way to tank a wall. 3:1 sand cement or liquid ones. Ignore roof overhang. Dont know why I typed that. 😨

 

[freddiemercurystwin]

So what level will the ground level be immediately behind your extension then? I thought it would be a foot above internal floor level?

where is the retaining wall at the moment?

 

[Bouba]

I have permission for 3 metre rear extension. The internal floor level will be a foot lower than the soil level if doing full 3 metre. If doing maybe 2.6-7 metre then a little gap remains.

At present just a half skin brick wall holding soil and the patio.