The latest Wild Croft project is Al’s “Timbertunnel” design, a timber-framed rigid polytunnel. The original was built for ourselves in 2022 but due to some great feedback on social media we’ve decided to start a separate business selling these.

Here’s some background info on why and how we built the Timbertunnel.

Timbertunnel Concept

I had designed a rigid polytunnel with the frame made from laminated timber several years ago, sketched it in 3D, costed it all out and then kept tweaking and modifying the design. But I never got to build it until this year. I wanted to design something that was made from locally grown timber but was also rigid and strong enough to cope with Scottish weather. Using twinwall polycarbonate sheeting adds strength and it will last far longer than conventional polytunnel sheeting. Recycled polycarbonate was also on the wishlist, but alas that’s not available yet (not in clear, anyway).

The Design

As it turned out, the design is not entirely new – the shape is fairly well used in the US, known there as a “gothic arch greenhouse” with plenty of self-build examples on YouTube, It was quite funny to stumble upon them, having been sketching and pondering something very similar for ages. There are a few examples in the UK that folk have made, too. It’s not really a “tunnel” as the curved sides meet at a solid timber ridge, which runs the full length. But ‘timbertunnel’ has a ring to it!

Here are the specs for my version;

  • Made from laminated Scottish-grown douglas fir, which is naturally durable (no maintenance)
  • Covered in 10mm twinwall polycarbonate, which has a lifespan >15years and also gives some insulation
  • Secured using heavy duty steel ground anchors, and does not require concrete foundations
  • Designed to last far longer than a standard polytunnel
  • Made to withstand strong winds and heavy snow
  • Most importantly, designed to look awesome!
  • If your land floods, you can flip it over and add a sail… (kidding)

The timbertunnel we built was 10.5m x 4.2m and has a central head height of around 2.6m. It has a large stable door at one end and a large window vent at the other end. Ours is not designed for raised beds, so it sits low to the ground and we will grow in the soil. Funnily enough my aim was not to make a beautiful boat-like structure, and definitely not to make a posh polytunnel!

Availability and Prices

Please visit for prices and availability.


There are many more photos of recent builds on the Timbertunnel site, but here’s our croft Timbertunnel.

You are welcome to visit us if you’re interested in seeing it and learning how it was made.


I am always happy to share, and will be selling plans for building your own timbertunnel. However please note that this design is my own and must not be copied or the plans used for profit or commercial purposes without written consent.