General FAQ

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Why should I use Prolam Glulam instead of steel

Here are just a few reasons:

  • Easier and lighter to handle and fix
  • Friendlier on the environment - stores carbon rather than emitting it
  • Uses NZ’s only renewable construction material - plantation timber
  • Uses 14 times less energy to produce than equivalent steel beam
  • Superior Fire Resistance compared to steel
  • Lower maintenance - Glulam does not rust or corrode
  • Cost effective - No boxing in or covering as with steel beams
  • Appearance - natural warmth and beauty of timber cannot be reproduced in steel
  • Will not buckle or distort in response to temperature changes
  • Direct fixing of plates, joists and other connections is much easier.

View our brochure on the benefits of building with wood here.

 

Why should I use Prolam Glulam instead of solid timber?

Because Prolam Glulam is manufactured from selected grade, kiln-dried material it is more stable than a sawn timber beam of the same section. The tendency of large section sawn timber to twist, split and shrink is greatly minimised in Prolam. A Prolam beam can reduce the overall section of members up to 40% compared to unseasoned timber, as they are pretensioned.

View our related FAQ video here.

What is the difference between PL8 and PL12?

PL12 has higher strength and stiffness properties and enables you to achieve bigger spans with larger loaded dimensions.

For a similar span and loaded dimension, a PL12 can offer a smaller section where the space is limited or aesthetics are important.

Can I substitute SG8 for PL8?

Yes. SG8 timber may be directly substituted with equivalent size PL8 PROLAM.

The strength and stiffness of glue laminated timber manufactured to AS/NZS1328

with a stress grade PL8 will exceed or equal that of grade SG8 timber.

What is the fire rating of Prolam?

The BRANZ appraisal states a charring rate from the table below.

  Density (kg/m3)        

  Charring Rate (mm/min)  

400

0.75

500

0.70

600

0.65

It is recommended that this simplified table of data derived from "White's" model and should be adopted for design of fire resistant timber structures in New Zealand. Prolam density is 550 kg/m3.

How much does the Prolam product weigh?

The weight of Prolam PL8 & PL12 treated to H1.2, H3.2 or H5 is around 550 kg's per cube. For example, the weight of a 240x88 H3.2 PL8 4.8m is around 56 kg. E.g. 0.240 x 0.088 x 4.8 x 550 = 55.76 kg.

Do you have Design Timber Properties ?

Yes these are available on Prolam website which can be found by searching "design properties" and in the Prolam structural timber guide.

What is the difference between LVL and Prolam/Glulam?

 

LVL (Laminated veneer lumber) refers to a manufactured timber product made from thin veneers (normally 2-3mm) glued together to form a beam. Prolam is a glulam product which is made from thicker sections of timber, generally 30-45mm thick, glued together to make a post or a beam.

Can I buy direct from Prolam?

All Prolam products are supplied through the main timber merchants nationwide as well as many timber specialists stores.

Click here to view our store locator. 

Do we provide pricing?

Yes, we do. We supply pricing and product through the timber merchants. If you're a builder, let us know your preferred merchant and trade account name, and we'll take care of getting you a quote for the Prolam you're after.

Where can I find the design properties of your beams?

Design properties are in the Prolam structural timber guide and can be found by searching "structural properties" on our website.

Do you have substitutions for Hyspan?

Yes. Click Here to download our comparison chart.

How dark can I paint my beams?

Prolam mustn't painted with any colours with a LRV rating of 45% or less to avoid risk of cracking and distortion of the timber.

What type of quality assurance comes with Prolam Glulam Beams?

All Prolam Glulam is manufactured to comply with the Australia and New Zealand Standard AS/NZS1328 and AS5096 - Glue Laminated Structural Timber A.

Can Prolam Glulam beams be used in exterior situations?

Yes. Treatment to hazard class 3 (H3.2 or H5) is recommended for all Prolam beams exposed to the weather. Along with this treatment an exterior adhesive resorcinol is used. The finished beams must be suitably coated with either a penetrating sealer or film-forming coating. When painting or staining external Prolam Glulam beams it is preferable to use lighter colours. Dark colours attract heat and may cause surface shrinkage. Because Prolam Glulam is chemically inert it is ideal for corrosive atmospheres such as swimming pools, marine structures, fertilisers and scouring plants where steel is subject to rust and corrosion.

View our related FAQ video here.

What is the classification of timber to be used for joint design as per table 4.1 of NZS3603?

The classification for Prolam products would be J5.