Raised bed against house

HoneypotCots

Looking for some advice on the logistics of building a raised bed against the the front wall of a stone rendered, 100 year old cottage. The stone gravel driveway will be going down this weekend for part of this renovation project but I'd really like to see a flower bed ar the front of the house rather than a mass of grey gravel drive or concrete path with pots so had my heart set on a raised bed...

In an ideal world I know this is not the thing to do but have read that as long as there's some form of damp-proofing between the bed and the wall of the house then we should be fine. We have already installed a French drain all around the house so the bed would sit on this and have stone walls.

Can anyone recommend the best way to go about this? Should we have a stone retaining wall just out from the house and fill with a shingle? Should hardcore be laid in the base of the bed?

Any information would be appreciated.

macraignil

You should inspect the wall to see if there is any sort of existing damp proof course. I have read that some walls were built with a line of slate at the base to keep the moisture from the soil from traveling into the wall of the house. If you are putting a flower bed at the base of the wall it would be important not to bridge this damp proof course and have soil in contact with the wall above this.

There is moderne PVC damp proof course that is sold in rolls that might be used as a barrier between the flower bed and the wall but you would need to be carefull not to position it so that moisture is kept in contact with your wall. I think a lot of old walls were built without a danp proof course and just rellied on better ventilation and open fireplaces to help dry them out. I think if you keep in mind that water should have somewhere to flow away from the house you shoud be OK. If you are intending on a retaining wall around the flower bed it might be worth leaving gaps between the blocks not filled with morter so water can flow out. Putting gravel at the bottom of the flower bed should help drainage and sounds like a good idea. Don't plant anything there that is known to have invasive roots or grow too big.

Good luck!

Discodog

I would always leave a gap. So build a separate rear wall an inch or two in front of the house wall. You won't notice the gap when it's planted.

recedite

HoneypotCots wrote: »

We have already installed a French drain all around the house so the bed would sit on this and have stone walls.

Its going to be too dry for plants, unless you keep pouring water in, which will seep down into the french drain.
Why does it have to be raised anyway? You could could just scoop out some of the gravel, drop in a plastic liner, and fill with compost.