Timber-framed grey water-processing greenhouse – part 2February 14th, 2014. Post by Quinta do Vale
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.