Glue Laminating at Grand Designs Live

This year CAT has been on bit of a promotional tour – travelling to London, Birmingham and London again to attend exhibitions, study fairs and conferences. Each event gave us the opportunity to talk to people about CAT’s work in the field of sustainability. From this coming Saturday however, CAT will be doing more than just talking.

We’re spending nine days camped out in the miniature village that is Grand Designs Live at the ExCel in London. Each day CAT will be providing demonstrations of glue laminating (or glulam) used to build the beautiful ‘wigloo’ you can see onsite in Wales. Jules, the carpenter who designed the toilet in association with Crafted Space, will be doing two demonstrations each day. As well as this, we have some examples of sustainable building techniques with us and the opportunity for people to ask CAT experts questions about their building woes.

Timber Arc Compost Toilet
The glue laminated compost toilet up at CAT

So what exactly is glue laminating?

It’s a process where several layers of timber are bonded together using a durable, moisture-resistant adhesive. The resulting structure can be used in both straight and curved configurations. The build that Jules undertaking requires curved lathes so he uses a ‘former’ to help hold the layers in place as the glue dries.


So why glue laminating?

Glue laminating has much lower embodied energy than reinforced concrete and steel, although of course it does entail more embodied energy than solid timber. However, the laminating process allows timber to be used for much longer spans, heavier loads, and complex shapes.

Glulam is two-thirds the weight of steel and one sixth the weight of concrete – the embodied energy to produce it is six times less than the same suitable strength of steel. Wood has a greater tensile strength relative to steel – two times on a strength-to-weight basis – and has a greater compressive resistance strength than concrete. The high strength and stiffness of laminated timbers enable glulam beams and arches to span large distances without intermediate columns, allowing more design flexibility than with traditional timber construction.

Glue Laminating
Jules clamping some glue laminated timber onto the former

We’ll be following the build live each day over on Facebook so have a look and see how it progresses!

If you like the look of the compost toilet, take a look at Jules’ website.

Grand Designs Live is open to the public from Saturday 4th to Sunday 12th May. More information can be found on their website.