Loft Ladder and Boarding Out

[polygonum]

Sometime in the next few months I expect to have to fit a loft ladder and board out a loft in a new house. The space will be used only for storage.

First question: What do I need to look for in a loft ladder? I have been using a cheap aluminium one in our current property. Nothing special but adequate. Should I just get something similar? Are wooden ones quieter or otherwise nicer? Any makes to go for, or to avoid?

Second question: One or other of the various legs for boarding out seem the obvious approach. There are several makes available. Which is best?

Third question: Flooring chip in suitable form (narrow, T&G) is readily available. Some is 18mm bit 22mm is also available. Does 22mm make much difference on the real world?

[Chris Hogg]

Piggy-backing on your query, what's the best form of loft insulation when boarding out? The recommended thickness of fibreglass insulation is 8" IIRC, but that's much thicker than the depth between the underlying ceiling joists and would be much compressed if boards were put over it, and would lose a lot of its insulating capacity. Do thinner slabs of rigid foam (Celotex, Kingspan or whatever) between the joists, achieve the same degree of insulation (resulting in a 'cold' loft), or is it better to put such insulation up between the rafters, resulting in a 'warm' loft. The loft I have in mind is quite drafty, so I guess insulation between the joists would be preferable.

[Tim Watts]

Celotex (etc) is about twice as good thickness for thickness as glasswool (or rockwool or sheepswool).

Personally I prefer it between the rafters, BUT you have to know the roof has sufficient ventilation over the top of the insulation otherwise condensation can form causing rot. As a guide, my BCO wanted:

1) 50mm air gap and soffit + top vents (tile or ridge) with sarking;

or

2) 25mm air gap and no vents with Tyvek type breathable membrane.

As I had to get the roof retiled I went for 2.

[Capitol]

I always loose lay 18mm chipboard cut from 8 x 4 sheets to rest on the joists. That way, you still have access to wiring etc. It was usefull last year when a pipe pinholed and flooded the loft insulation, so that drying it all out was relatively easy.

[Charles F]

An improvement on that is seconds of cellotex/kingspan laid over the joists, and loose T&G chipboard over the top. This gives you reasonable access later, and is a cost effective increase in the insulation. The PU foam sheets are quite solid enough to support the chip over the joists with no fixing of either.

100mm of glass or rockwool between the joists and 50 or preferably 75mm of PU foam gives you the equivalent of 200 or 250mm of glass/rockwool, which while not quite up to current building standards will make a huge difference to your heat losses.

If you do need to get up to current standards 100mm or two layers of 50mm PU foam over the joists will do it, and for our extension the buildings inspector was quite happy with that.

Charles F

[David]

One thing - we had the loft opening enlarged to be able to take 8 * 4 sheets without cutting down.

We also used a wooden loft ladder (from B&Q) because it was much more substantial than the flimsy aluminium jobbies.

Cheers

Dave R

[polygonum]

Appreciate the thought, but no pipes up there.

[polygonum]

Thanks but it will already be to current standards. So no need to change the insulation and probably very poor payback for any additional measures.

[polygonum]

I don't think I could manage getting 8x4 sheets up there!

At a quick glance, the only wooden ladder at B&Q is a Werner. Is trhat what you got - and are happy with?

[PeterC]

+1 for the loft hatch. I got one wit an integral ladder (note: can't reall insulate it as the ladder is close to the hatch) and that fitted, almost, 2 spacings. Although 4' would go diagonally, I was on my own and couldn't lift and manipulate 8x4. Used 2' water-resistant T&G chipboard from Wickes (a piece left outside in rain suffered no ill effects). I cut the tongue back to the first shoulder and took off some of the bottom of the groove, so that there's still some engagement but boards can be lifted. No extra insulation, as I didn't want to lose headroom - at 6' 4" I need all I can get. I am tempted to add 30mm to the joists: support the ceiling with props to give a bit of pre-load, glue and screw 30mm (true) to the nom. 75mm (3" supposedly) joists to clear 100mm, then use 100mm Celotex (can't use 75mm as the joists are about 72 - 73mm in places) all sealed a a vapour barrier. Replace the boarding and that should be an improvement on 75mm of compressed G/F.

[tabbypurr]

Compressed girlfriend? What's going on over there!

NT

[John Rumm]

Any within reason will do the job. You can get some nice wood ones with wide treads that are more like a folding staircase. Pricey and more work to fit, but a much more comfortable "climb".

Having said that, I would tuck rockwool etc between the joists, then lay PIR foam boards over the top, and place the flooring directly on top. No need for legs then, and less lost height due to the better insulating properties of the foam.

Go for the lightest...

[tabbypurr]

it would probably be fine, but does carry at least some risk of interstitial condensation. You shouldn't really put a foil barrier on the colder side of insulation, which it would be there.

I can't see any possible point in 22mm for a loft.

NT

[John Rumm]

I might if the joists were on 600mm centres...

[PeterC]

Self-inflating though ;-)

[PeterC]

Managed to find the (equivalent) of the one that I fitted. It has a 159kg rating and is easy to lower and raise. I removed a length of a joist and fitted a new piece as th gap was about

80mm to long. The span is only 2m and the joists are well supported there, so I reckoned it'd be OK. the 100x700 one.

I had to rig up a method of operating the ladder and hatch from in the loft, as I couldn't lift, position and fasten the frame on my own with the ladder in place. The springs are very strong so couldn't be replaced with the hatch open.

[PeterC]

I used 18mm on nominal 400mm centres. Tried a bit only about a foot wide across a gap of about 450 - 500mm with gentle bouncing on it and it was OK, so much wider pieces on 450 are OK - feel solid.

[polygonum]

Thank you, PeterC. That might be spot on.

[Roland Perry]

In message , at 22:05:15 on Fri, 13 May 2016, polygonum remarked:

Get one with step-by-step instructions. No, seriously, that's what was written on the ones which came with mine.

[Fredxxx]

I like my wooden ladder. It feels more sturdy than an aluminium one and a key point is it has wider, more pleasant treads.

I see nothing wrong with 8ft x 2ft t&g, unless you ever want to get to upstairs wiring etc. I used 8" x 1" PAR after shopping around so trivial to unscrew a board to get to a light fitting from above..

Either way, mark in pen where the cables are!