How to seal my Masonite siding at the seams?

by Ann32538622

Good morning. I have vertical Masonite siding on my home. The sheets are four feet wide and the seams overlap. The seams were not sealed before painting when the house was built but I’ve been told those seams need caulked. It’s time to paint the house again and I’m wondering if caulking is really necessary.

  4 answers
  • Kathy Gunter Law Kathy Gunter Law on Sep 19, 2018

    Caulking would be in your best interest. It is an economical step and it keeps out insects and the elements.

  • Ken Erickson Ken Erickson on Sep 19, 2018

    You could possibly get away without caulking, but a few tubes of caulk is a cheap price to pay to improve air and water infiltration.

  • Lifestyles Homes Lifestyles Homes on Sep 19, 2018

    Oh yes indeed it’s necessary. The seams will swell & never go back down if not sealed. Then they will begin to break down and spall at the seams over the years.

    Caulk is cheap compared to this scenario.

  • Diane Coverdale Diane Coverdale on Sep 20, 2018

    A UV resistant silicone sealant should work, but find out which type of formulation would work best with the type of paint you are using.