Frequently asked questions about glulam
To help any new or existing customers navigate the world of glulam we have listed a range of frequently asked questions to help. If you can’t find the answer to your specific question, we’ve also listed contact details for our team below.
What is glulam?
Glulam is an abbreviation of glue laminated timber. It is made by bonding together layers of timber using a very durable adhesive. Lots of smaller layers are stuck together to make a larger piece of timber.
Can I purchase just one glulam beam from you?
Yes – we are happy to receive any size order from a glulam lintel to a complete glulam warehouse.
Is glulam sustainable?
Yes – the embodied energy of timber is much lower than most alternate construction materials such as concrete and steel. The use of locally grown timber in particular can further reduce the carbon footprint by reducing the haulage impact. We also think there’s an argument to be made that there’s a benefit to increasing the use of locally grown timber to stimulate the economy of this sector – better prices for growers will lead to more trees being grown. We are certified to supply FSC® certified products sourced from responsibly managed forests. We are also certified to supply PEFC certified products from sustainably managed forests. Read about the carbon footprint of glulam.
What is glulam used for?
Glulam is used in construction to provide a framework for buildings in the same way that steel is used but with better sustainability credentials. Because of glulam’s aesthetic, natural qualities unlike steel it is often left exposed as part of the interior decorative scheme. Basically, wherever steel or concrete is used in a superstructure, there is potential to design an alternative in glulam. We’ve used glulam for a huge range of structures – see our portfolio for more details.
What is a glulam portal frame?
Portal frame structures are designed to span between supports and rely on fixed joints with moment resisting capacity to give the frame stability. Portal frame structures can be constructed using a variety of materials and methods.
Is glulam as strong as steel?
When looking at strength to weight ratio, glulam is actually around 3 times stronger than steel! Steel does have a much higher allowable stress, so steel members tend to be smaller than the equivalent glulam member, but the glulam is usually lighter. Please refer to our load span tables or talk toy one of our engineers if you want to calculate a size.
Can glulam out-perform steel in a fire?
Where steel distorts in high temperature the surface of timber will char at a known and predictable rate. This means glulam can be designed to have a certain time of fire resistance without the need to apply any further materials, whereas steel would need to be boxed in or have an intumescent paint.
What is the difference between glulam and CLT?
CLT – Cross Laminated Timber – is a form of glulam which can be simply described as ‘giant plywood’, and is used to make panels rather than beams. The term glulam is usually used to refer to beams, not panels.
Is glulam’s carbon footprint smaller than concrete?
Yes – glulam has a sixty per cent lower carbon footprint than concrete.
Is glulam stronger than ordinary timber?
Yes – because we are able to cut out some of the natural defects, and due to the averaging out effect of lots of layers in the glulam meaning that a defect can’t run as far through the section as in sawn timber. Smaller glulam sections have less of an increase in strength in comparison with sawn timber, but larger sections of glulam can have a strength increase in the order of 40%.
How far can you span with glulam?
As a guide, thirty metres – but glulam beams can span much more than this. One of the greatest advantages of glulam is that it can be manufactured in a wide range of shapes, sizes and configurations.
Can glulam beams get wet? Can glulam beams be used externally?
Yes – but, like any other structural application of timber, it will degrade if it is not correctly protected. It is important to ensure glulam is treated with the correct finishes (varnish/stain etc). There is a wide range of finishes available to protect glulam including oil, varnish, water-based stain and fire treatments. Glulam can be used externally if suitably treated and maintained, we recommend larch or Douglas Fir glulam for external use.
How much does glulam cost?
Glulam is more expensive than non-laminated timber. This is because there are a large number of stages involved in the manufacturing process. Our glulam beam and glulam structure price calculator can give you a quick budget price.
Is glulam cheaper than steel?
For a simple beam, spanning between supports, glulam is often cheaper than steel. There is often also a saving due to the ease with which you can fix joist hangers, etc. to the beams, and the fact that you don’t need to box the glulam in as you would do with steel. For fabricated structures glulam is usually a little more expensive than steel.
Can I build with glulam straight out of the ground?
Where possible always ensure that there is no direct ground contact. We usually design galvanised steel base brackets to lift the bottom of the glulam off the ground. Click here for more information on glulam connections.
What size of glulam beam do I need?
This depends on the span and loading. You can refer to our load span tables or give us a call to talk to one of our engineers about calculating a beam size – we can often give you a preliminary size over the phone.