Hi
I am just now laying the first layer under my extension, which will have a cast slab as the foundation.
There are small gaps between some of the boards.
Is it something I need to worry about & need to seal in some way?
How important is it & tips on how to seal if necessary.
No matter how I do it, it doesn't come out completely right.
I am just now laying the first layer under my extension, which will have a cast slab as the foundation.
There are small gaps between some of the boards.
Is it something I need to worry about & need to seal in some way?
How important is it & tips on how to seal if necessary.
No matter how I do it, it doesn't come out completely right.
The common practice is to lay the boards with staggered edges between the layers. I don't think it's common to seal around all boards more than trying to get them to lie as tightly as possible. If it's a single layer, boards with tongue-and-groove edges are usually used. It's also not uncommon to place a plastic sheet on top of the bottom layer for extra moisture protection.
I use foam sealant in those gaps. That seals and at the same time glues everything together so it doesn't move. Is it necessary? Probably not. 