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• Timber Supply for Oak Frame Houses
• Timber frame for supermarkets
• The quandary of externally exposed oak frames
• Oak frame and building budget
• Infill panels and building warranty

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Timber frame for supermarkets

September 23, 2009  · Posted by Scott Fotheringham

In my blog about the In Touch with Timber conference recently, I touched on the building of large timber framed supermarkets. I assumed that retail giants like Tesco and Sainsbury were motivated by profit and nothing else in a very competitive market, so it pricked my interest that timber space frames are now more financially attractive than steel to the commercial sector, as is so often the case in continental Europe. Could this be the kick start for a major expansion of the timber engineering industry in the UK?

First and foremost it appears, getting people into the supermarket is the primary objective of the retail sector. Once people are in they spend. Everything the supermarkets do is customer led. Environmental or "green" issues are very fashionable. People feel good about helping the environment and want to be green, and look favourably on companies that are also trying to be green. So the supermarkets are now competing with each other to be greenest. Tesco announced plans to spend £100m on research into wind, solar and geothermal power, twice as much as Gordon Brown promised in the last budget. Interesting that Mark Soutar, Head of Environmental Construction for Tesco said that they got more publicity by sticking two little wind turbines on the roof of one of their stores which only powered the signage than any of their other environmental measures.

Anyway back to the engineered timber building. Apparently, with the massive rise in steel prices closing the gap, it is still more expensive to build in timber. So why is timber more attractive to large retailers? The timber trade says: 

• It is good to have a viable, renewable alternative to steel should steel become unavailable or unaffordable in the future. Recycling of steel uses huge amounts of increasingly more expensive energy. With timber you turn the building into pellets to fuel the biomass boilers, and make new glulam with fast grown trees planted specifically for the purpose.
• The price of steel has risen dramatically with the rise in energy costs making timber much more competitive, something that can only continue.
• Customers appreciate the positive contribution that visible timber construction elements make in terms of a warmer and more relaxed environment.
• Timber has a vastly reduced impact on the environment, due to its carbon content (the carbon storage effect) and the lower energy required producing, processing and transporting the material.
• Better performance in fire.

All of which are true of course, but the supermarkets say:

• Supermarkets are built around services, and fixing services is far easier, quicker and cheaper in a timber building.
• Green initiatives attract customers, customers spend and we profit.

I say:

• For whatever reason the research has been done, the template stores have been built, and with all this private investment and hard work they have kick started the large clear span commercial timber building market.
• Good for the timber trade, and most importantly good for the environment. I've never quite understood the logic in the green claims about recycling steel, when you consider the massive amounts of energy required. Thank you to the retailers for taking the initiative.

 

More blogs by Scott Fotheringham

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The quandary of externally exposed oak frames

September 16, 2009  · Posted by Andy Parker

In response to my blog in July several people have asked how to achieve an externally expressed frame without continually breaking the thermal envelope of the building.

Our view is don't make the oak frame part of the thermal envelope because the only guarantee you'll get is that it will leak somewhere at sometime. In how many places and how often will depend on the skill with which a system is fitted but all the systems we see are extremely complicated with lots of components. In other words they're prone to human and component failure.

Although some 'purists' don't like the idea, the best way to achieve current building regulations and get the appearance of an externally expressed frame is to use air dried oak cover boards over a complete external thermal envelope.

There are a number of products to which one can apply render and if the cover boards are fixed to the panels first the render then 'fills' between the cover boards so that they aren't so obviously surface mounted. Be sure to use good thick cover boards to prevent cupping. Below are some pictures of a really well executed 'externally expressed' frame using this approach. This new oak framed house is in Twyford, Hampshire.

The rear elevation of this new oak framed home in Hampshire demonstrates the use of cover boards to create the externally expressed frame

Thick cover boards prevent cupping so this exposed oak frame will look good for many many years to come.

As an aside I find it difficult to see what's 'purist' about an oak frame that uses numerous modern components to try and make it meet current regulations!

 

More blogs by Andy Parker

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