Boarding of loft after new insulation has been laid

[staithes14]

I have contractors coming on Friday, to lay new insulation (part of the government grant scheme). I've emptied the loft accordingly, but they tell me that the new insulation will be well above the level of the joists, and I would like to re-board the loft afterwards, without compressing the new insulation, as we really need that storage space.

Is there a best way to go about this? All I can think of is to cut through the quilt to find the joists, and screw blocks on top of them, to support loft boards. I fully expect it to be a right pain in the backside.

 

[kbdiy]

You've left it a bit late to be honest. The new insulation will be 11" deep (270mm) so you will need to build up at least 6" or more, depending on the depth of your joists to avoid compressing the insulation.

Some firms use quilt but others blow the insulation in (looks something like cottonwool). Either way you're right - it will be a pain to do after the event.

 

[staithes14]

They said it would be quilt. Is this likely to be laid between the joists or over the top of them?

 

[freddiemercurystwin]

First layer should go between then subsequent layer should go perpendicular to the first, then perpendicular to that one.

 

[staithes14]

Right, so I'll need to do some cutting to get to the joists. Ah well, needs must.

 

[freddiemercurystwin]

You should be fitting new joists perpendicular to your existing really rather than chunks of joist to spread the load better. But if you’d done that the installers would likely refuse to do the installation.

 

[WabbitPoo]

As stated, you dont have to cut the insulation as it will be running parallel to your new joists that you'll be installing. Just squidge the insulation about so you can fit the joists where you need them. Make sure you (and they) don't obscure power cables or any recessed light fittings in the process.

 

[staithes14]

Someone's said I should try 'loft legs'. Are they a good idea? Never heard of them but I have looked them up so get the idea.

 

[big-all]

i dont like legs they cause point loading and because its not 2 parallel bits off wood that will spread the load over a large area
if you assume the wood is 400mm apart the span is 400mm
with legs at 400mm apart the span is then 40% more at 560mm because the span is now the diagonal