Working on your knees in an attic for long periods of time can be very hot and tiring.
Roof rafters 7 insultaion.
For instance if the roof has 2 by 6 rafters and you want r 30 insulation which is standard in many communities you can add a 2 by 4 which will give you an 9 inch rafter space.
If you have an easy roof to vent and decide to go that route you could use mineral wool insulation between the rafters and beneath the vent channels.
If 180mm is to be installed then 100mm board might be introduced between the rafters there has to be a minimum 25mm air gap between the insulation and the underside of the tiles or slates with an 80mm board running.
The battening and tiling is then fixed down over.
Kingspan with a warm roof the usual process is to split the insulation into two layers.
As this requires fitting insulation above the rafters the roof covering will have to be removed in order to fit the insulation.
This roof type will require a breathable membrane like kingspan nilvent to be.
If you choose or need to go with an unvented roof you would need either exterior insulation or a flash coat of closed cell spray foam first then you could round out the insulation package with mineral wool.
The insulation can be placed between the rafters or it can be placed between the ceiling joists.
The insulation is placed over the rafters and then a felt is placed on top.
You will be covered from head to toe in clothing and gear.
The roof will typically be insulated above the rafter line creating what is most commonly known as a warm roof.
To create a warm pitched roof insulation such as kingspan kooltherm k7 pitched roof board should be fitted between and over the rafters.
In part 7 you ll learn how to insulate the attic rafters.
In part 6 of this series on attic insulation we dealt with proper attic ventilation and how it goes hand in hand with proper insulation.
This method of installing roof insulation allows you to maximise the headroom by using a thinner layer of insulation beneath the rafters.
Modern u value targets mean installing insulation between rafters only is rarely a viable option.
Utilising a pitched roof as a usable living space is an effective way to maximise the square meterage of a residential development.
It allows insulation to be installed in a watertight roof either after the roof covering has been fixed on a new build or without disturbing an otherwise sound existing roof covering as part of a renovation.
There will also be kooltherm k7 pitched roof board between the rafters image credit.