Shed/Play house on Decking

[Harto]

In January I installed a playhouse on decking. The decking sits on four piles of breeze blocks embedded in the ground and there is a weed membrane down. The shed floor is two sheets of ply sat on 5 x 2 inch square timber floor bearers.

We have now noticed that the floor inside the playhouse is getting damp by the sides of the playhouse above where the floor bearers run. I have contacted the retailer who has contacted the supplier.

They have advised that the damp is caused by the floor bearers soaking up water from the decking. Their advice is to fit a damp proof membrane between the decking and the floor bearers. To my mind though this will only make things work since the water will not be able to drain away between the decking boards but will sit on the dpm until it evaporates or is soaked up by the floor bearers.

Does anyone have an opinion on the advice I've been given? Also, if their advice is incorrect any advice on how to resolve the problem. I guess the only idea I have is to remove the house, remove the floor bearers and put a dpm between the floor bearers and the ply floor before putting it all back together again.

 

[freddiemercurystwin]

So you laid a timber floored shed on timber bearers and you're surprised the floors getting damp?

Again, you're surprised by this?

 

[Harto]

So you laid a timber floored shed on timber bearers and you're surprised the floors getting damp?

Again, you're surprised by this?

Thanks. So helpful.

If the decking was sat on a concrete floor, it would more than likely be sat in a puddle so at least on decking it drains well. The decking is dry.

If you know so much why don't you suggets a solution instead of poking fun?

 

[freddiemercurystwin]

put a dpm between the floor bearers and the ply floor

 

[big-all]

i always advise something at least 25mm thick[slab or suchlike] then dpm or roof felt before you get to the wood

any 2 surfaces will trap water