Insulation - Help needed asap!!

Vitamin C

Hi, need some advice if anybody can help it would be much appreciated.

Last week attempted to insulate my girlfriend's mother's attic, and I think I made a mess of it. The house was cold before, and my girlfriend and her mam think it's colder since the insulation went in.

So, I closely followed instructions from a friend of mine who recently insulated his Da's attic successfully, but after reading some of the threads on here I think he was full of sh*te.

So here's what I did:

The joists are 4 inches deep with around 600mm between each joist (far bigger than standard I realised). With chipboard flooring on top of them, only in the centre, about a third of the total area, directly below the apex.

Firstly, I stuffed the eaves above the fascia to stop any breeze getting in (my friend told me to do this, I'm now worried it was a bad idea after looking on here).

There was ancient fiberglass between the joists about an inch thick, which I left there, again under instruction. I then measured, cut and rolled out 6 inch fiberglass between the joists, taking up the chipboad in the middle, rolling the fiberglass across, then screwing the boards back down, slightly squashing the fiberglass below it by two inches or so.

Also, I didn't tack insulation onto the trap door. And finally, there was one roll of extra insulation left over so I rolled it out on top of the first layer on one side of the attic, horizontally to the first layer.

So to summarise, the entire attic is insulated with 6 inch yellow fiberglass between 4 inch joists, on top of old fiberglass, an inch or so thick. About a third of the whole area is the covered with chipboard slightly squashing the fiberglass below it. The ventilation all along the eaves/fascias has been stuffed with fiberglass. No insulation on the trap door.

I have a feeling that everything I did was wrong, if anyone has any advice or opinions please let me know, it would be very much appreciated.

Thanks

Colm

FesterBeatty

Dont panic...

Yes it should be ventilated as you pointed out, but you've introduced 6 inches of insulation to the entire roof space, how could that possibly make it colder??!

Temperatures have been dropping on a daily basis since last wednesday or so, so naturally the oul wan is going to feel colder in the house.

With regard to the 100mm joist at 600mm centres, I expect that this is not a joist but rather the bottom boom of a truss, in which case it sounds typical of most traditional timber trussed roof. The purpose of the chipboard strip in the middle is just to give you safe access for storage, i.e getting the christmas tree etc.

In summary, I'd make good on the ventilation issue but I don't see how anything you've done could possibly make the house colder whatsoever.

rayjdav

+1 to Feaster above but,

Trap Door: Staple plastic to board and tack insulation, 2 layers staggered to it on top. Draught seal the edges. Otherwise all heat will just fly up there, wasting a lot of time/effort/expense.

Also, is there a water tank up there? If so make sure to insulate this, totally wrapped but allow for warm air from below.

Vitamin C

Thanks for putting the mind at rest lads.

@FesterBeatty...I had mentioned that about the temperature dropping alright, but the suggestion was met with the "hmmm" that we all no so well! Cheers for the advice anyway, I'll unstuff the eaves immediately anyways.

@Rayjdav...thanks for your reply, there's a brand new water tank up there which the installers insulated really well with that blanket stuff, I put a little more underneath it around the edges too. I'll do up something for her trapdoor too.

Do yis think it would be worth getting a couple of extra rolls of fiberglass just to roll out on top where there is no chipboard for good measure or would it make any difference?

rayjdav

Vitamin C wrote: »

Do yis think it would be worth getting a couple of extra rolls of fiberglass just to roll out on top where there is no chipboard for good measure or would it make any difference?

Imho the chip board, as I understand your situation, is doing more damage to the fresh quilt roll. It is pressed down thereby losing a lot of it's intended insulant properties so, if it was me, I'd insulate to beat the band with loads more where you can but remember, you can spend your lotto winning on the attic but if the rest of the house, walls/doors are not up to scratch, your not going to really gain an awful lot. To get the real benifits, it must all be of the same standard.

who what when

Vitamin C wrote: »

So to summarise, the entire attic is insulated with 6 inch yellow fiberglass between 4 inch joists, on top of old fiberglass, an inch or so thick. About a third of the whole area is the covered with chipboard slightly squashing the fiberglass below it. The ventilation all along the eaves/fascias has been stuffed with fiberglass. No insulation on the trap door.

Currently to get to a B1 standard you have to put in 12 inches of fibreglass insulation (just to give you an idea of the current standards).
Now thats not to belittle your efforts which should most certainly have made a difference. If it was my house i would have put 6 inches between the joists (as you did). But then i would take out the chipboard altogether and come along with another layer of 6 inches rolled in the opposite direction.

Just to clarify something. You said you put 6 inches under the chipboard along with the original 2 inches and then squashed it down to the thickness of the joists, ie 4 inches. Well i hate to break it to you but this still only counts as four inches of fibreglass insulation! In fact you can get 3 feet of it and squash it down to 4 inches and what youre left with is still no better than just putting in 4 inches worth.
The 'puffyness' of fibreglass insulation is hugely important and shouldnt be squashed down under any circumstances.

As regards the old lady, ignore her. People can be so ungrateful sometimes.

L driver

+1 to the replies
It is a test.... the ma isn't sure on you yet. Keep your council young man. Turn on the heat when she is out, things nice and toasty when she gets back.... otherwise you might end up as her HOT WATER BOTTLE:D maybe that is what she wants? devious things them oul wans:eek:

FesterBeatty

If it was me I'd just buy her a new jumper for christmas!

Hannibal

I have a rear extension roughly 13x15 feet that was never insulated, last January in the freeze it was like an icebox. I had a six foot double rad in it and could still never get the heat into the room.
So this summer I took down the ceiling, insulated it with six inches of the rockwool type covered it with plastic then reslabbed and plastered it. Ii also has three external walls so I put up the 1.5inches of that insulated plasterboard the whole way around while adding a new seven foot double rad. The room is now like the Costa del Sol, even in this weather the gas heating is regularly getting knocked off. The point being the walls are as important as the ceiling. Even in an attic i'd recommend insulating between the roof joints with the foil back kingspan like insulating as nothing will then escape from your attic.

martin46585

FesterBeatty wrote: »

If it was me I'd just buy her a new jumper for christmas!

one of the nice itchy aran jumpers..........

Vitamin C

Haha, cheers lads, let's hope I won't end up a hot water bottle anyways!

I'm gonna seal up the trap door and roll out some extra rolls where there is no chipboard, they need the attic for storage so there's no way I can take it up altogether.

They have a conservatory directly below my girlfriend's bedroom which is like a freezer, and the door out to it is wooden and glass double doors with no seals, so I reckon they're loosing a lot of heat there. The walls are fairly thin too with not much of a warming board on them, they had a damp problem in my girlfriend's room (no need for any innuendos lads!) which could be a lot of the problem too.

Anyways, my mind is put at rest so thanks lads!

Lantus

1/ Unblock the vents, prevents moisture and mold inthe loft.
2/ Insulate the loft hatch.
3/ Consider putting an airtight strip around the loft hatch and also go around the windows and see if they can be done. Did it a few years ago and it makes a world of difference.
4/ Front door is a weak point. draughts are rife here. weather strips make a huge difference.
5/ keep all doors closed.
6/ use a timer to keep the heating on every so often during the day to keep it up to temperature without using excessive gas/fuel.
7/ check rads are bled and hot to the top. (do this when heating is off!)

wouldn't worry too much about compressing insulation under boards if it's a really small area. Is insulation nice and snug against joists? i.e. no gaps, you shouldn't be able to see the ceiling underneath.

As previsouly stated we are having some very cold weather so subject to where this house is it could well be having a positive effect and you just dont notice.

BostonB

Should the eves be filled with insulation. Mine aren't and I think its bringing cold air down the walls.

rayjdav

BostonB wrote: »

Should the eves be filled with insulation. Mine aren't and I think its bringing cold air down the walls.

Yes, BUT, it is VERY important that there is 50mm (2") of an air gap between the underside of the roof and the insulation to allow for free air movement from the vent in the soffit to the attic area, allowing for breathing of the timbers.

Poor Uncle Tom

Just a note on attic ventilation:

Most of the soffit vents are fitted by the PVC fascia and soffit lads as they see fit and not in accordance with any design plan. Most of the attics I've seen are over ventilated. It is important to get a cross flow ventilation working in your attic but it needn't be like a gale force nine crossing the Tundra up there.

BostonB

I think mines over ventilated. The attic it self isn't that bad, but some of the walls are freezing.