So you’ve decided to build your extension or house incorporating a beautiful bespoke green oak frame which features lots of traditional carpentry, exposed timbers and soaring trusses, but just as important will be how you decide to insulate and clad the structure.
Historically oak frames were exposed externally and internally with lime rendered infill panels of wattle and daub. This system can still be achieved but there has been a move away from such methods for two important reasons: firstly it is becoming more and more difficult to meet exacting energy efficiency requirements for providing well insulated and airtight homes when the oak structure cuts through the insulated envelope creating a whacking great “cold bridge”, and secondly, dealing with the natural shrinkage of green oak makes it almost impossible to prevent an infill panel system from leaking (air and water!)
So what’s the alternative?……SIPs (Structural Insulated Panels)
SIPs are a sandwich comprising 2 layers of structural board bonded to an insulated core. The structural board is made of OSB (Oriented Strand Board) and the insulated core is either expanded polystyrene or rigid urethane.
More and more projects are choosing to sacrifice the external aesthetics of the oak frame in favour of an insulated envelope made from Structural Insulated Panels which wraps around the oak frame. Such a construction method has so many benefits, it’s hard to know where to start
We work closely with our SIPs partners to coordinate the panel design and the oak frame to ensure that the dry shell and the frame fit. Manufacturing is also synchronised so that the SIPs shell erection can proceed as soon as the oak frame has been raised.
We have two SIPs companies who we work with and can thoroughly recommend:
Just down the road from us in Hereford, Glosford Timber Solutions are delivery partners for market leaders Kingspan Tek SIPs. Kingspan (again another local company) have been making their own 144mm rigid urethane sip panels for many years, and have recently developed a thicker 172mm panel giving u – values of 0.14
If you're considering an oak framed building (or larch, or douglas fir), let's talk. We'll gladly put together an outline quote (completely free, with no strings attached). And we need very little information from you to do so.
Equally, we're always here, at the end of the phone, to talk through your ideas.