Installation Guide
Page 3
Butt Joint Gapping Requirements
32° F and 
below
33° F to 74° F
75° F and 
above
3/16" gap 1/8" gap 1/32" gap
Installing TimberTech
® 
Decking
Extreme Heat Warning
Be aware of excessive heat on the surface of TimberTech 
products from external sources, such as but not limited to, 
fire or reflection of sunlight from energy-efficient window 
products. Low-emissivity (Low-E) glass can potentially harm 
TimberTech products. Low-E glass is designed to prevent 
passive heat gain within a structure and can cause unusual 
heat build-up on exterior surfaces. This extreme elevation of 
surface temperatures, which exceeds that of normal exposure, 
can possibly cause TimberTech products to melt, sag, warp, 
discolor, increase expansion/contraction, and accelerate 
weathering.
Current or potential TimberTech customers that have concerns 
about possible damage by Low-E glass should contact the 
manufacturer of the product which contains Low-E glass for a 
solution to reduce or eliminate the effects of reflected sunlight.
Excessive Construction Debris
It is important during construction, the deck’s surface stay 
clear from excessive build-up of dirt, sand, and dust from tile, 
concrete, landscape blocks, or any other masonry products. If 
these materials are not removed immediately, the deck surface 
will become difficult to clean and can potentially damage the 
deck’s surface finish. 
If a build-up does occur please refer to the Care and Cleaning 
section in TimberTech’s installation guide or website, 
www.TimberTech.com. 
Calculating Material Requirements
To determine how much TimberTech decking material you will 
need, start by calculating the square footage of your deck 
surface by multiplying length by width. Once you know this 
number, divide it by the numbers provided below for 12’ planks, 
16’ planks and 20’ planks.
Once you know the square footage number, divide it by 5.5 for 
12’ planks, 7.3 for 16’ planks and 9.1 for 20’ planks.
When calculating the amount of decking you will need, it is 
recommended that you add roughly 10% to the total for a 
scrap factor. 
Example: Length x Width = Total Square Footage
Square Footage ÷ by 5.5 (12’), 7.3 (16’) or 9.1 (20’) = Planks 
Needed (Round the number up)
Planks Needed + 10% (Scrap Factor) = Final Number of Planks 
Needed (Round the number up)
Working With TimberTech Planks
Gapping Requirements For All TimberTech Planks
• Side-to-side plank gapping must be minimum 1/8” to 
maximum 3/16”.
• For California fire requirements, please refer to page 15.
• Allow 3/16” minimum gap where the planking meets any 
adjoining structure or post. 
• Follow these butt joint gapping guidelines for all TimberTech 
planks: 
Expansion and Contraction
TimberTech deck planks will experience expansion and contraction 
with changes in temperature. Expansion and contraction are most 
significant where extreme temperature changes occur. Fastening 
the deck planks according to the gapping requirements noted in 
the following table accommodates for this movement. 
Changes in length are most significant during the installation 
process, and should be accounted for if working in extreme 
temperatures. A good example would be cutting your planks 
during a hot afternoon, letting them sit outside overnight 
in the cool air and then installing them the next morning. 
Chances are, you will notice a certain amount of contraction. The 
best way to minimize this problem is to fasten your 
planks as soon after cutting as possible.
Access Installation Resources 24/7.
Installation guides and videos are available on our web site at www.timbertech.com/installation. 
Do you need help with your installation?
We have an excellent customer service team that is here to help you with your installation questions. If you need help  
you can call customer service at 1-800-307-7780 or visit www.timbertech.com/installation to view TimberTech installation videos.










