Yes. All H3.2, H4 and H5 treated Prolam glulam is pretreated before laminating which means the post or beam is fully treated throughout and does not need a paint-on treatment applied to a cut portion. However, the timber and any cuts must be coated as per the Prolam coating requirements.
Refer to Holes in Laminated Timber to ensure any holes drilled do not affect the glulam structurally.
Yes, Prolam posts can be cut to the required length, however the cut ends do need to be sealed with a moisture-resistant sealer, stain, or paint to prevent moisture ingress into the end grain and protect the structural timber.
Each laminated piece is treated before the post is glued together, so treatment runs throughout the post even after cutting or sanding. Sealing is still recommended for added protection.
Refer to the Prolam Coating Requirements for further information.
Yes. It is recommended to seal the in-ground portion of Prolam posts to help prevent moisture ingress. The same paint or stain used on the above-ground section can be applied for consistent protection of the structural timber.
For best results, follow our Prolam Coating Requirements.
Any Prolam glulam product that is exposed to the weather at any time should be coated (even if it is inside the building envelope) to prevent timber from absorbing moisture. Prolam glulam products should be kept dry with wrapping and/or cover before installed, and sealed before and during installation.
Refer to the Prolam coating requirements for further details.
Yes, it is important to coat Prolam exposed timber before installation to prevent moisture ingress and preserve aesthetics and durability. This also applies to any cut ends or joins.
Prolam glulam can be stained using an oil or painted using an enamel paint. These products must have an LRV rating over 45%.
You can view our coating requirements and recommendations here.
Yes. Prolam glue laminated timber can be painted or stained to match the aesthetic. In fact, any exposed timber must be painted or stained with an oil based coating to preserve aesthetics and durability. This is optional for Prolam glulam timber used in internal applications.
Yes. A Prolam H5 post can be installed directly into the ground without a concrete surround. However, the post must be properly sealed using Sika Bitumen, stain, or paint to retain the warranty and help protect the structural timber from moisture ingress.
Prolam glulam beams and posts should not be painted with colours below a 45% LRV rating, as darker coatings can increase the risk of cracking or distortion in structural timber.
Refer to page 3 of the Prolam Coating Requirements for further information.
To maintain Prolam glulam posts, beams, and other exposed structural timber products, refer to the Prolam Coating Guidelines for full instructions on preparation, application, and recoating intervals. For additional guidance, refer to the manufacturer's coating instructions on the product packaging.
Yes. Installation guides are available for Prolam products including glulam beams and posts, as well as our PLX bracing solutions, the PLX Portal and PLX Column.
Installation guides can be found in the Technical Section of the website and in the Product Downloads section on each product page.
Surface checking is a natural behaviour of engineered timber. As Prolam glulam absorbs and releases moisture, the outer fibres move more than the core, which can cause small surface splits. These checks may appear or fade with changes in weather. They are superficial only and do not affect the structural performance of Prolam structural timber beams or posts.
Wrapping on Prolam engineered timber is designed to protect against marking during handling and transport, not as waterproof protection.
For indoor storage, leave the wrapping on until the timber is required. If outdoor storage is unavoidable, remove the wrapping, place timber fillets between posts or beams, then rewrap or cover with a waterproof sheet.
Moisture can become trapped beneath wrapping, so it should be slit to allow drainage. Wrapping may remain on during construction to prevent damage, but partial removal can result in uneven weathering or discolouration.
Minor surface checking in Prolam glulam is a natural response to moisture movement and is cosmetic only. Small checks can be filled using a 2-part Norski epoxy glue, or where the timber will be painted, a flexible filler such as No More Gaps or Perma Filla can be used.
No. Splits or openings along a glue line in Prolam glulam do not necessarily mean delamination has occurred. They are often caused by natural checking as the engineered timber responds to changes in moisture. In larger timber sections, these checks commonly occur along glue lines where the timber fibres are interrupted and can be mistaken for delamination.
Delamination is the separation of the timber from the adhesive bond. If you look into the opening, natural checking will typically show rough or torn wood fibres, whereas delamination will appear as a smooth, flat separation along the glue line. You can also check the depth of the opening by gently inserting a thin card or feeler gauge.
If delamination is suspected, contact the Prolam technical team for assessment and advice.
It is important to only use fixings for Prolam glulam timber that have been specified by the engineer's specification or PS1. Ensure galvanised or stainless options are selected depending on indoor/outdoor use and timber treatment. Don't fasten too close to edges or ends.
Common suppliers we recommend are MiTek, Pryda, Simpson Strong-Tie or SPAX.
For MCA H3.2–H5 treated glulam timber, Prolam recommends a minimum of 304 stainless steel fasteners, nails, and screws for all exterior or exposed structural timber applications. This is because MCA treatment can accelerate corrosion in standard steel fixings, and stainless steel provides the durability needed to maintain structural integrity over the long term.
Surface checking is a common feature of timber products and can occur as Prolam glulam absorbs and releases moisture in response to environmental conditions. Because the outer fibres dry and shrink more quickly than the inner core, small surface splits may develop.
The appearance of these checks can change with the weather and seasonal conditions. In most cases, surface checking is cosmetic only and does not affect the structural performance of the Prolam glulam member.
Apart from our glulam exposed truss, pergola and PLX bracing solutions which include fixings and connections, Prolam does not sell fixings. However, you can find our fixing recommendations for use with our products here.
You can purchase these at your local trade store, e.g. PlaceMakers, Carters, Mitre 10, ITM, Bunnings, BuildLink etc.
Prolam glulam beams can be supplied with a factory-applied sealer to reduce moisture absorption. If left exposed to weather for more than 8–10 weeks, an additional coating should be applied.
For long-term protection of Prolam structural timber beams or posts, follow our full coating requirements here.
For subfloor framing, H3.2 glulam must be at least 150mm above ground. H3.2 glulam posts should not be in contact with the ground as the treatment does not prevent moisture absorbtion.
If you suspect delamination in a Prolam glulam member, contact the Prolam technical team as soon as possible for assessment and a remediation guide before attempting any repair. Delamination differs from natural surface checking — refer to our FAQ on checks and delamination for guidance on how to tell the difference.
Yes, you can drill or notch a Prolam glue laminated beam but only if it has been specifically detailed by the engineer or using the Prolam Specifier. Unapproved holes and notches can void compliance and compromise structural performance of engineered timber.
Ensure holes are small and drilled in the middle third of the span, centred vertically and never at the beam ends or where supports or fixings are required
After storing in a flat and dry location and ensuring your posts and walls are level, you can begin installing your Prolam glulam beam.
Using appropriate lifting gear, move the beam into place, and then secure the beam using fasteners recommended by your engineer or Prolam. Keep heavy materials off the beam until it is secured.
For full details, Click Here to download the design and install guide.
If the glulam beam is an exterior exposed beam, ensure it is coated as per the Prolam Coating Requirements prior to installation.