The last post on this build finished with the laying of the chestnut ring beam which forms the base of this sweet chestnut timber frame construction. The next part was to raise the main supporting structure.
The challenge of building a timber framed greenhouse onto the main building here, half the way up a mountain as we are, has been the minimal amount of space we have to work in. The area in front of the existing building is only around 3m wide before there’s a 2-3m drop-off down to the next terrace which itself is barely 2m wide at that point before dropping down into the stream. The height of the timber frame is 4m, so laying the assembled cross frame (or bent, for American readers) on the ground to raise it in traditional block-and-tackle style was impossible. It’s also impossible to get any sort of heavy machinery anywhere near: access to the front of the building from either direction is via footpaths barely a metre wide.
Our only option was to raise the first cross frame very literally by hand. With the wood still being green, each of the three 4m sweet chestnut main timbers was insanely heavy on its own. We had no idea whether it was even going to be feasible to contemplate lifting three of them as a piece. If it couldn’t be done, then Rick would have to figure out a way to assemble the cross frame piece by piece in situ which, in any case, would have to be done for the second one since it’s sited less than a metre from the terrace edge.
We had 6 guys on the lift and 3 on the safety rope wedging themselves inside the building. After a practice lift to waist height just to establish whether everyone thought it could be done, they went for it.
Rick’s precision joinery meant that the mortise and tenon joints fitted exactly … with a bit of persuasion.
With the first cross frame in place, the remainder of the structure went up like this …
Yes. The building is this close to the terrace edge.
Joints are secured with oak pegs.
This is a two-storey greenhouse.
Working at the edge required some careful handling of the timbers.
Safe to say that Rick is pleased with his work.
First set of principle rafters in place. This took us up to mid November 2013.
karina February 15, 2014
My God, what a project and a half! I can’t wait to see the end product, Wendy! :)
Ted Leger April 7, 2014
It definitely will be something to see once it is finished. Or has it been finished already? This post is two months old.
Quinta do Vale April 7, 2014
Not yet Ted. The frame is done and dusted and has been for some time and the pine sarking is done too but with the guys here helping me out part time while they work on their own projects, progress here is never rapid. We’ve also had a run of bad weather so the tarps aren’t coming off until it’s drier. Up-to-date stuff is on Facebook if you’re interested and there’ll be a post here once the roof is back on. (Please note I will delete links to commercial websites. Comment spam isn’t tolerated here.)
Simon July 19, 2014
Very nice! Interesting to see you have used chestnut (not oak or pine), did you mange to get it locally?
Quinta do Vale July 23, 2014
Sweet chestnut is the traditional timber for building in this area. It grows in these mountains and all the wood was locally sourced, though it wasn’t easy to get the larger pieces as most is brought to the woodyard in standard lengths and we had to negotiate for some of the longer spans from standing timber. Traditionally, timber for building was grown in deep ravines on the north slopes of these mountains to encourage trees to grow straight and tall. The chestnut prefers the north slopes and it grows slowly enough to form good timber there. This tradition is dying out though because reinforced concrete beams are now preferred over chestnut for building and the remaining chestnut woods are being harvested, often to be replaced with eucalyptus for pulp (which is an ecological disaster and fire hazard into the bargain).
The oak varieties that grow here aren’t as strong as sweet chestnut and they don’t grow as straight and long. They’re nothing like English oak. Pine is possible and the local Maritime pine is decent building pine. But there’s an enormous number and variety of wood-boring insects here with voracious appetites, so it’s less than ideal unless you’re prepared to slather it in gallons of noxious chemicals.