Loft Insultion vs Rafter insultation

[mcmike]

Hi,

I have recently bought a house and I am in the process of considering what my options are to insulate the house. The house was built in 1889 and has a new Slate roof and new roof rafters.

Option 1 - tradtional loft insulation - 270mm deep, however the joists aren't very deep so i would loose the use of the loft as a storage space.

Option 2 - Rafter level Insulation - Kingspan Insulation sheets would probably be what i'd go for this would enable me to board the floor of the loft and use it for storage.

I welcome an opinion on both options, or in fact if people have other options that i haven't thought of.

Would either of these options leave me open to more damp?

Thanks for reading and I look forward to hearing about your thoughts.

8)

 

[mointainwalker]

How much storage space do you need and how much is it worth to you ?

Option 2 will be a lot more expensive and require more skill and more time.

It will also mean that you will have higher heating bills because

a) You will be heating the loft space as well as the house
b) You will not be able to install as much insulation as you could on the
floor.


If you only have "normal" storage needs, why not insulate the storage area up to the top of the joists and the fully insulate the rerst.

If you decide to insulate the floor, then lay a vapour-barrier over the joists and ceiling to prevent moist -air from the house rising into the loft and condensing.