Some Arizona houses were built with wood siding, normally called T1-11. Bought in big sheets 4×8 or 4×12 these sheets can cover lots of SF very easily. A few cuts to accommodate what you might have on your wall, things like windows and doors, dryer vents, hose bibs or exterior outlets and your installation is complete. Easy right?

We recently had a project request to do an overlay of Hardie Plank over T1-11. Customer was having woodpecker issues for years. he kept on replacing the siding every few years but got tired of doing so. He noticed that his neighbor who had the same issue did something different to solve the problem and he wanted in.   


The Response Crew Team Installing Hardie Planks


Damage to T1-11


One of the downsides of T1-11 is that it can easily be damaged. We see things like weather damage or woodpeckers poke holes in the middle of the sheet. In this case, you really only have 2 options, replace the sheet or a section of it, or do an overlay. 


What is an Overlay and should I do this?


Overlay is simply to install a new sheet over the old sheet. Although there are no code agents doing an overlay, you should be very careful when choosing this option. 

Here are some questions you should ask before making up your mind. 

  1. What material should you choose? 
  2. How do you overlay without getting moisture trapped between the 2 layers. 
  3. Can the original install carry the weight of a second layer
  4. What type of joints should I have


You decided to do an overlay, should you use Hardie Plank?


This product is a great product and I see it being used more and more. It is made out of fiber cement mix and will never rot (unlike plywood) or get eaten by termites, it is durable, long lasting and can be ordered painted with a 30 – 50 year warranty. Normally you would paint a house every 10-15 years and plywood will never last that long.  


Is Hardie Plank more expensive?


Yes, when you compare the cost of Hardie Plank VS plywood or vinyl siding, hardie plank is around 3X the initial cost. But you know what they say, you get what you pay for. 

Hardie Plank takes longer to install, requires house wrap when done on studs and because of the weight, it is a crew job. Vinyl is cheaper on labor and product, easy to maintain and long lasting although not as long as Hardie Plank. Vinyl is easier to cut making the install a lot quicker. Both Vinyl and Hardie Plank will out last plywood.