Decking Weed Membrane

Gary Fletcher

Gary Fletcher

Gary Fletcher

Associate
Joined
15 Jul 2021
Posts
2
Location
Rochdale
Hello.

long story short I’ve done my sub base and built my deck using 6x2. If I can attach a picture I will. I have taped all my joists with deck tape.

my dilemma is to put the weed membrane on top or below. My issue is I laid a few composite deck pieces down to show the mrs and even though it’s only a 4mm gap I can see my joists through them at certain angles.

I understand why they say don’t use weed membrane on top , air flow etc but will the deck tape not reduce that issue to literally null ?

thanks for your advice
 
Weed membrane needs to be in contact with the ground to minimise weeds growing through. It'll be less far effective suspended in the air as inevitably light will get through the gaps or over time it'll get damaged then the whole area will have light through to it and start to grow weeds. All decking has the joists visible at certain angles and is completely normal.
 
Putting one down seems a bit OCD anyway. We don't have one down under ours, just hard core and no weeds grow as the earth isn't getting any sun light.

You could put one down and put hard core or pea shingle over the top.
 
Membrane in ground contact. Should have put it down before doing all the joists. See if you can get someone to help and lay it as best you can and overlap where possible. Use more than you need but keep it on the ground and staple it down. Once done then if all the joists are taped you shouldn’t see them in gaps. I used some epdm tape to cover some bits of blocking rather than full deck tape to ensure it was not visible between boards.
 
If you put membrane on top of the joists you will get all kinds of dirt sat on top of it between your decking. Stones, leaves, dirt. And it will all be visible. Much better if all that muck just falls in.
 
You must log in or register to reply here.
Back
Top Bottom