Adding purlins between heavy timber trusses is an elegant way to reduce the cost of a timber frame roof because purlins permit an increased on center distance between trusses so you purchase fewer trusses.
How to insulate heavy timber frame roof.
This arrangement forms cavities that can accommodate.
Plastic or tarpaper is applied on top of the sheathing.
Normally the insulation is either built up above 2x ceiling roof decking that is installed on top of the trusses or sips structural insulated panels are installed on top of the timbers the range of insulation is dependent on the thickness of the sips or of the built up insulation.
I used 2x6s for the framing toenailing the 2x6s into the roof system.
Roof insulation as well as roof ventilation is a topic that comes up in our daily conversations with our clients.
2 x 4 or 2 x 6 rafters are then placed on top of this assembly.
On top of the ice and water shield we start framing out a cavitiy to hold insulation.
This saves money and time.
In a built up roof 2 inch lumber is secured to the exterior side of the finish ceiling and covered with standard sheathing materials.
It is also known for some of the craziest weather extremes and weather swings in the country.
The roof can also be framed and insulated using this technique.
Sheathing is placed on top of the roof timbers.
There are several ways to insulate the frame.
When insulating between timbers you have to be able to cut insulation easily and quickly so that it fits tightly against the timber frame and also against the inner surface of the frame be it osb or a membrane.
Timber frame truss and purlins.
2x2 stringers and 3 4 rigid insulation on the inside creating a channel for soffit to ridge venting plank drywall the inside and blow it full of nice cheap eco friendly celullose insulation.
You only insulate over the interior of the cabin all the overhangs are left free of insulation.
What is the correct way to insulate and ventilate a log or timber frame construction roof.
Wools glass fibre mineral natural fibres are the best way to insulate between studs simply because they are compressible.