Find out how to repair mortar. Get tips on consulting with a mason to match the mortar recipe. Learn how to repoint bricks, starting by raking the joints.
LESLIE: Well, brick or concrete walkways and even steps, they look fantastic. I mean they really can dress up a house. But over time, you know, the mortar between the bricks or those blocks can weaken and then start to crumble.
TOM: That is the weak link. But the good news is the problem can be fixed and here to tell us the step-by-step on how to do just that are Kevin O’Connor
, host of This Old House
and general contractor, Tom Silva
So Kevin, let’s start with you. What’s your take on the issue?
KEVIN: Built properly, stone, brick and concrete block are some of the most durable building materials around. But they’re held together with mortar and, over time, the mortar can fail.
TOM SILVA: You’re right. The mortar will fail and it’s usually because it’s exposed to water; water running down the side of the building because someone didn’t replace the downspout; or splash-back – when water runs off the roof, hits the building, it actually pulls that mortar out. And fortunately, it can be repaired. But when repointing a building, it’s most important that you match the recipe of the mortar that’s existing. So you’ve got to find a mason around that maybe worked on the building; they know what kind of cement they’ve used. Or you can have it analyzed and they’ll tell you the right proportions of sand, lime and cement.
KEVIN: OK. So let’s talk about the steps of repointing a brick wall. Walk us through it.
TOM SILVA: Well, repointing or sometimes called tuckpointing is when you push new mortar into that joint. First thing you have to do is clean out the joint really well. You can use a chisel or you can use a raking tool and that actually draws out the loose mortar, the old mortar. And you want to get it about an inch deep because you want to make room for the new mortar.
TOM SILVA: Alright? So once you’ve cleaned it out, you’ve got it all brushed out, now you’re ready to mix up the new mortar and push it into there with a pointing tool which is a very narrow trowel that will fit the space between the block and the brick. Push it in there nice and tight. It’ll match the joints around it, match the profile. A concave joint is better than a flat joint because it sheds the water better.
KEVIN: Alright, and it’s a job you’ve done quite often and we’ve got a step-by-step video on ThisOldHouse.com.
TOM: Along with point-by-point instructions. (Kevin and Tom Silva laugh)
Tom Silva, Kevin O’Connor, thanks for stopping by The Money Pit.
TOM SILVA: Thanks, Tom. Nice to be here.
KEVIN: Good to be here, Tom.
LESLIE: And for more great tips, check your local TV listings for This Old House which is brought to you by Lumber Liquidators, a proud sponsor of This Old House. Lumber Liquidators – hardwood floors for less.