Worried about glulam damage or repair? Quick answers to common glulam rehabilitation questions.



Glulam is structurally engineered to rival materials like steel and concrete, so it’s an incredibly strong and durable choice of material for construction, from joinery projects to providing structural frameworks in buildings.

In fact, glulam performs better than steel in some circumstances such as corrosive coastal or swimming pool atmospheres and when exposed to fire.

Like any material, factors such as age and environment can result in some degree of deterioration over time, but maintenance and repair options can avoid the need for replacement. We recently spent some time on the rehabilitation of a glulam base in Cornwall and thought it would be helpful to answer some of the most common questions about glulam’s life expectancy, including how to spot signs of damage and what action to take.

Click through the photos below to see the process from start to finish…

How long does glulam usually last?

Glulam can last for much more than 50 years without requiring attention. Unless it has been subjected to extreme moisture (if it has been left in the rain without protection, for example) or it has been incorrectly specified, it will remain structurally sound.

Water damage is by far the most common reason for degradation of glulam.

What signs of damage should I look out for?

Glulam is an engineered wood product and water damage is bad news for timber. If you have had an undetected leak onto your glulam beams over a long period of time, you will see telltale signs of moisture on the surface of the timber. This would usually be a degradation of any coating on the glulam, black mould spots and a softening of the surface of the timber. If you can easily drive a knife blade or screwdriver into the timber, this indicates weak spots in your glulam and must be addressed. You should also establish the source of the excess moisture and prevent it from re-occurring.

Glulam can tolerate some degree of damage, such as longitudinal cracks along a portion of the beam, which are sometimes caused by a drop in moisture content (drying out) after manufacture. However, if you notice cracks that join up along the full length of the beam, or cracks in the side of the beams more than 1/3 of the width, you should consult a specialist.

Can glulam beams be repaired?

If damage occurs to a key structural element, a full replacement may not be necessary. With our expertise, it is often possible to intervene with minimal disturbance at a much lower cost than rebuilding the entire structure.

Glulam beams that have been continuously subjected to wetting and drying, or beams with cracks along their whole length, may have deteriorated so far that they need to be fully replaced.

How do you repair a glulam beam?                     

The first step is to assess the damage, ensure you stop any further ingress of water, and ask for help from glulam experts.

Small parts of most beams can be fixed by cutting away the damaged portion within the original glue lines and inserting replacement pieces or using epoxy resin. It’s usually much easier to repair glulam compared to timber and the work will be scarcely visible.

In other cases, we might add additional laminate pieces to strengthen existing beams.

Sometimes it may be necessary to insert steel shears or tension strengtheners, or to lift the toe of the damaged post and insert steel flitch beams to lift them above the water damage level.

If the original glulam beam had been treated for weathering or with a fire retardant, the new parts used in the repair should also be treated in the same way.

It is very important to make sure any substitute pieces have a comparable moisture content to the original glulam beam and that the correct glue is used.

How much does it cost to repair a glulam beam?

It can cost surprisingly little to repair a glulam beam – much less than the expense of replacing a large part of a complex structure.

Usually it is a quick process, taking from half a day unless gluing is required, in which case overnight drying time will be necessary. Factors that will impact the cost of repair are the distance to site, accessibility, and the complexity of the repair.

Can you recycle glulam?

If glulam has been well-preserved (usually by keeping it inside and away from moisture), valuable old pieces can be re-cycled and used again. Solid timber in good condition can also be re-cycled into laminated timber.

Some structural timbers can be recovered and recycled into furniture, particularly oak and valuable hardwoods.

We’re here to help.

If you have any questions about the use of glulam or have any concerns about the condition of your existing glulam beams, please get in touch – we are the largest manufacturer of glulam in the UK, and we have a team of expert designers, structural engineers, carpenters, and joiners who can help!