When james hardie siding products butt into wood based materials a 1 8 gap will allow for expansion and contraction of the wood based product.
Best caulk for hardie board siding.
James hardie also does not recommend applying caulk to the horizontal overlap between siding planks see figure 2.
Once all caulk is dry and your siding is clean you ll paint hardie plank with a high quality exterior grade acrylic latex.
In this article i ll talk about the caulk sealants i personally used.
Pros and cons of painting hardie plank.
Without further ado let s get on with it comparison of our best caulk for hardie string.
152 4 mm wide 1 in.
Wherever hardie siding meets a trim board the company recommends you leave a 1 8 gap between the siding and the trim and apply a 3 8 bead of approved caulking to protect and seal the edge of the siding.
We only caulk butt joints on cedar siding if previously caulked.
Caulking around windows doors eaves and trim edges gives added insurance that leaks will not occur.
Joint flashing butt joint horizontal lap treatment june 2014 james hardie does not recommend caulking butt joints or the horizontal overlaps joint flashing 6 in.
Then make sure the coating is completely dry before applying the 2 nd coat.
So what i would tell you to do is to use a colored caulk to choose the caulk in the color of the siding.
You can use this sealant anywhere and on any kind of surface from cement to wood metal to plywood.
It s got good adhesion and expands and contracts.
But you are correct that it is very difficult to paint.
25 4 mm on overlap no caulk figure 1.
Fiber cement boards are caulked only when there is no metal flashing behind them.
Trim boards wood windows.
So here i am telling you about the best caulk for hardie siding.
But most importantly i ll share my experience about what you should and shouldn t do.
Best caulk for fiber cement siding or hardiplank siding lets you have the perfect sealing your surface needs.
A professional exterior painting expert will use a spray application for a smooth factory like finish.
Some manufacturers do not require the metal flashing therefore we caulk the butt joint to keep the pieces together and also prevent moisture.
That is why we are showing you some other products for various surfaces along with our top pick.