Attic Insulation

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One of my Projects for 2019 is to get around to get my Attic insulated, I have being in the house for 12 years and every winter i notice mold on the ceiling, and want to try and solve the issue once and for all.

My house is a Semi-Detached 3 bed room house build i say in the 60's

In-order to achieve this I was looking at:


Floor:

200 m insulation roll

using 2x2 Timber going 90 degrees in order to put another 200 m between them the 2x2 Timber wood would be in-order to place Attic Floor boards down for storage.

Roof:

100 m Thermawall Insulation boards for between the joists

Should i also place something like 50 m Thermawall insulation boards across the 100 m boards ? or something like a Thermawrap ?

Wall:

Using 100 / 150 m Termalwall insulation on the attic walls:


Any thoughts on the above will this be enough ? Also can i claim from the SEAI if this is a DIY job ?

Lumen

Insulate the floor OR the walls and rafters. Not both.

the_pen_turner

2x2 wont hold up any kind of weight.
use kingspan sheets to build up a solid area to put stuff. put ply on top of it to make it stronger

docker.io

the_pen_turner wrote: »

2x2 wont hold up any kind of weight.
use kingspan sheets to build up a solid area to put stuff. put ply on top of it to make it stronger

Thanks for the reply

Only items I have are the Christmas decorations. And a few other items. So using 200m rockwool for the floor then across that Put 100 or 50m kingspan then lay down ply wood.

I was going to use 2x2 I can even use 2x4 across the floor that would allow me to use rock wool, using extra sheets for kingspan would increase the cost of the project

docker.io

Lumen wrote: »

Insulate the floor OR the walls and rafters. Not both.

What would be the risk to the wood if I did the rafters and floor and left walls as is ?

It seems the norm to insulate your attic ceiling

the_pen_turner

rock wool is needlessly expn=ensive and horrible to use. ecoze or similar is great stuff.
i would do 400mm minimum

if its only a few boxs i would buy 1 4" sheet of kingspan and cut it in half and put some ply on top. it needs to hold your own weight incase you stand on it and go down throught the ceiling

893bet

Lumen wrote: »

Insulate the floor OR the walls and rafters. Not both.

Why?

Outkast_IRE

You should go away and do a small bit more research before starting this project. For a standard insulation job you will get the loft rolls and lay them across the joists , assuming you already have 100mm full fill between the existing joists .

If you have this existing insulation check it's installed correctly with no gaps and it's in contact with the ceiling . I'm my own attic when I moved in it had 100mm insulation but was poorly laid over wires etc so it wasn't in contact with the ceiling and this offering no insulating value.

So
1. Assess condition of existing insulation if it's less that the depth of the joists then replace.

2. Decide what thickness you are going to insulate to , I recommend 150 to 200 mm . The rock wool is dear for what it is , for a standard loft roll bandq and similar offer very good value on buying 3 rolls at a time for equivalent thermal performance as to rockwool.

3. For storage as I only needed a little I opted for loft legs / stilts with loft boards on top , by far the easiest DIY option for a small storage area.

4. Don't forget to insulate pipes, water storage cisterns, heating expansion tank, and at a minimum get a draft strip for the attic hatch and have a think about how you want to insulate that , I decided to use a thick sheet of self adhesive nitrile insulation I had for another purpose.

Outkast_IRE

893bet wrote: »

Why?

Most attics are ventilated, with outside air via soffit vents, so insulating the rafters does nothing as it's outside air between the ceiling insulation and the roof.

This is typically called a cold roof construction and most homes in Ireland are built using it, if you cut off the outside air ventilation you are creating a warm roof structure which your roof is not designed for and will almost certainly lead to condensation forming in places you don't want it to form unless specific measures and systems are installed to control it.

If doing loft insulation ensure your soffit vents are not blocked accidentally.

Lumen

893bet wrote: »

Why?

If you insulate the floor properly the attic will be cold because it is unheated and ventilated. The roof insulation will then be pointless. If you want a warm attic, insulate the rafters and walls, but you need to be careful with ventilation.

The only argument to do both is if you want to keep the attic sometimes at a different temperature from the rest of the house, e.g. an attic conversion occasionally used as a guest bedroom. But then you'd need zoned heating, deeper joists, protected escape route etc, so it's no longer an insulation question.

docker.io

Lumen wrote: »

If you insulate the floor properly the attic will be cold because it is unheated and ventilated. The roof insulation will then be pointless. If you want a warm attic, insulate the rafters and walls, but you need to be careful with ventilation.

The only argument to do both is if you want to keep the attic sometimes at a different temperature from the rest of the house, e.g. an attic conversion occasionally used as a guest bedroom. But then you'd need zoned heating, deeper joists, protected escape route etc, so it's no longer an insulation question.

Thanks, I am 5'7 and can't stand up within the attic so I assume the height of the roof may just be over 5 foot, so making this into an attic bedroom is out of the question.

I did notice a tear on the panel sheeting under the tiles. Is this something that needs to be dealt right away ?

Zebrano

docker.io wrote: »

Thanks, I am 5'7 and can't stand up within the attic so I assume the height of the roof may just be over 5 foot, so making this into an attic bedroom is out of the question.

I did notice a tear on the panel sheeting under the tiles. Is this something that needs to be dealt right away ?

Yea get this fixed this is probably whats causing the mold on the ceiling.
I had the same thing im my old house and since its fixed there has been no mold.
Make sure u shop around for roofers as i found the proce varied wildly and one was being really pushy and was under the impression that i wanted it done there and then when i clearly stated on the phone it was for a quote.

docker.io

Zebrano wrote: »

Yea get this fixed this is probably whats causing the mold on the ceiling.
I had the same thing im my old house and since its fixed there has been no mold.
Make sure u shop around for roofers as i found the proce varied wildly and one was being really pushy and was under the impression that i wanted it done there and then when i clearly stated on the phone it was for a quote.

How much did it cost you to get that fixed And would your insurance cover the cost ?

Unlikely, I know, but is the The Better Energy Warmer Homes Scheme any use to you?


http://www.citizensinformation.ie/en/housing/housing_grants_and_schemes/warmer_homes_scheme.html

Zebrano

Cant remember exactly but i had to get the whole length of felt replaced across the front of the house so was probably a more involved job than u need
And no insurance wont cover it

docker.io

Zebrano wrote: »

Cant remember exactly but i had to get the whole length of felt replaced across the front of the house so was probably a more involved job than u need
And no insurance wont cover it

were they able to do the job under the tiles or did they have to come off ?

Zebrano

they had to take off the first 3 lines of tiles