Loft insulation

enigma27

enigma27

enigma27

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Essex
Hi All.

been trying to figure out why our upstairs rooms don't get up to the same temp as down stairs and think I may have stumbled onto where the heat is being lost.

So this is the amount of insulation we have in the loft between the joists.. some places its flatten down others are not to bad but only looks like its 60-70mm in places and 100 in others..

TSfjesM.jpg


would it be best to rip this lot out? some of it has gone black where some egit decided to pack it in the eves blocking all airflow causing condensation which i sorted out last year.

Not sure whether to start a fresh or just use whats there and overlay with some 170mm on top.. I have a floored storage area also so I am guessing rip that up and raise the floor height with some legs and floor back down?

and recommendations on good insulation that's not overly expensive?

also would it be an idea to use the foil quilt and cover over the roof trusts? i did this recently with my conservatory so have some left over.
 
I removed the existing stuff in mine but not sure how much value it adds in terms of insulation, also adds a lot of dust /effort. Only going to improve if the new stuff has a better U value. Depth will be the main factor.
 
I left the rockwool that was down (100mm) and put another 140mm sheepswool over the top that I got given. Whether it made a difference or not I have no idea :p Rooms have high ceilings and still cool down very quickly, although it has coincided with the outdoor temperature dropping quite a bit
 
Buy a load of rolls when its on offer, top it up. Its cheap, and rarely on the government deals anymore.
Very little point in removing the existing, just adds hassle/mess, simply add above.

Top up to in line with joists/above, then go 90 degrees different and do side to side across.
The more the merrier, its cheap and a one time job..

If you think you might ever possibly maybe want storage up their, now is the time to add the floor risers and put the floor in raised above insulation. DONT squish the insulation with floor, leave about 10-20mm air gap.
 
thanks all.

I need to remove the water tank and beams that were installed to hold it as its not used anymore.

has anyone used the plastic legs to raise the floor? or would wood beams going across the joist work any better?
 
I went over the top of the existing insulation with kingspan insulation boards in my loft, sitting them on the joists. It has the added advantage you can then just float a chipboard floor over the top of it instead of needing the plastic legs.
 
enigma27 said:
has anyone used the plastic legs to raise the floor? or would wood beams going across the joist work any better?
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I kitted the central space in ours with 'loftlegs' from homebase, then boarded on top.
As you can imagine, particularly difficult to get started but when you have a few down, it's a fairly straight forward but also cost effective way of retaining heat and maintaining somewhere to store items.
 
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enigma27 said:
has anyone used the plastic legs to raise the floor? or would wood beams going across the joist work any better?
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Yep, I did mine the other month. I used the loft legs with loads of screws and loft boarding. Topped the insulation up to 270mm throughout as well. Decide on what you want to do, be certain, and do it in one. Its not a job you want to be going back to and changing. Very messy and dusty.
 
I used timber instead of loft legs, running at 90 degrees to existing celing joists.
I just didn't trust those plastic legs (although I'm sure they'll be fine)

I have since converted my loft to a usable space and half of it now has its own floor with 8x2 timber used for joists, the bit that I won't be standing on as much still has 4 x 2 joists laid across the existing ceiling joist, I pre-drilled and drove 200mm timber screws through. I actually have my timber joists resting on top of a piece of 4x2 on its side to raise the joist up enough, this was done more to clear CH pipework that for height though.
 
enigma27 said:
thanks all.

I need to remove the water tank and beams that were installed to hold it as its not used anymore.

has anyone used the plastic legs to raise the floor? or would wood beams going across the joist work any better?
Click to expand...

Yeah I posted it here.
Bungalow build log

To be fair, if you've got easy enough access to put in long timbers I'd feel comfortable doing it either way now. I don't have any concern about the structural stability of mine though, given its a crawling space thus the load is going to tend to be fairly spread regardless.

I'd recommend a drill/impact driver if you do it
 
Glad I found this thread as it's something I've been putting off doing for the past couple of years! In a similar position to the OP as I have about 100m of the yellow stuff already there and I was going to just lay some extra over the top which has already been suggested in the thread. Is there a preference as to which rolls to buy or are they pretty much all the same?

However, I have half of my loft already boarded and so I was thinking about taking up the boards and putting something like the Celotex stuff down and then putting the boards back on top. Or, would I be better putting the plastic legs on, more rolls on top of existing and then boards on top?
 
zom247 said:
However, I have half of my loft already boarded and so I was thinking about taking up the boards and putting something like the Celotex stuff down and then putting the boards back on top. Or, would I be better putting the plastic legs on, more rolls on top of existing and then boards on top?
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You shall have to do your sums. Celotex stuff is more expensive than conventional loft insulation. Look at the insulation ratings of both products and add in the cost of the legs (they're rather expensive for that they are). I think it would probably be cheaper getting the legs.
 
topgun06 said:
You shall have to do your sums. Celotex stuff is more expensive than conventional loft insulation. Look at the insulation ratings of both products and add in the cost of the legs (they're rather expensive for that they are). I think it would
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Cost not really a major factor - I'm all for the easy option :)

How many legs do you need per board? It'll probably take me quite a while to do the legs route as I'm still recovering from a knee op and can't kneel down too long at the moment.
 
zom247 said:
Cost not really a major factor - I'm all for the easy option :)

How many legs do you need per board? It'll probably take me quite a while to do the legs route as I'm still recovering from a knee op and can't kneel down too long at the moment.
Click to expand...
Celotex is actually harder to fit, because you have to cut it and make sure there are no gaps and that it is a snug fit, whereas the stuff on a roll (evil horrible stuff), you can just roll out where you want it, I would imagine you could do a full loft in no time.
 
MassiveJim said:
Celotex is actually harder to fit, because you have to cut it and make sure there are no gaps and that it is a snug fit, whereas the stuff on a roll (evil horrible stuff), you can just roll out where you want it, I would imagine you could do a full loft in no time.
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It would be quicker roll over so the unboarded half will take no time at all. Doing the boarded part will be far slower as I'd have to remove the boards, fit the legs, roll out and then fit the boards on the legs. Not sure if I'll get round to doing the boarded area this side of Christmas but I could roll some insulation over the unboarded part. Removing all the stuff from the loft will be the hardest part, I've got tons of boxes up there so it'll be a good excuse to have a clear out.
 
zom247 said:
Cost not really a major factor - I'm all for the easy option :)

How many legs do you need per board? It'll probably take me quite a while to do the legs route as I'm still recovering from a knee op and can't kneel down too long at the moment.
Click to expand...

I'd go with the stuff in a roll then. Once the legs and screwed down it is very quick to install the insulation. I went with 6 legs per board. And yes, lots of kneeling down required unfortunately.
 
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