What waterproofing does
Good sealer turns rain away from joints. It soaks into brick and mortar. It lines the pores. Water beads and runs off. Damp air inside can still escape as it dries. That one-way flow is the whole point.
Walls need to breathe. Brick takes in some damp no matter what. If damp cannot get out, frost pries the wall apart each winter. The right sealer stops liquid rain but lets vapor pass.
From the walk, sealed walls look the same. No shine, no film, no change in tone. The guard is in the pores, not on the face.
Signs your walls want it
- Walls take driving rain with no roof overhang.
- Chimney or parapet joints wear fast.
- You just paid for repointing and want it guarded.
- White crust keeps blooming on brick.
- One wall stays damp long after rain.
How it works
Step 1: We check the walls. Joints must be sound first. Sealer over bad joints is wasted.
Step 2: We wait for cure. New mortar needs weeks to dry. Sealing too soon locks damp in.
Step 3: We clean the face. Grime and haze come off so sealer soaks in even.
Step 4: We spray or roll it on. Two light coats beat one heavy coat. The wall drinks what it needs.
Step 5: We test the bead. Water is misted on to show the beading. You see the guard work.
What never goes on brick
Paint traps damp. Thick coats trap damp. Clear films trap damp. Water still finds small cracks. Then it cannot leave. Winter does the rest where you cannot see.
On soft old brick this ends badly. Faces pop off in sheets. We turn down jobs that ask for film sealers. The quick sale is not worth a ruined wall.
What shapes the price
Wall area leads. More face means more sealer. Wall state counts. Dirty walls need more prep. Height adds setup. Some walls need two trips.
Each home weathers its own way. Every project is different — contact us for a free written estimate.
Chimneys gain the most
Stacks take weather from all sides. Their joints wear first. Sealer after repointing buys them years. Parapets are next. Then windward walls.
Calm, roof-sheltered walls may skip it. We say so when that is true. Honest scope beats a bigger ticket.
How water gets into brick
Brick is thirsty. A dry brick can soak up surprising amounts of water through its pores. Mortar joints drink too, especially as they age and craze with hairline cracks. Wind-driven rain pushes water deeper than still rain ever could. The west and south walls of a Baltimore rowhome take this beating for decades.
Parapets are the worst entry point on many buildings. They catch rain from above and both sides, with no roof to shelter them. Their caps crack with frost. Water pours straight into the wall core. It travels down inside the wall and shows up as stains in rooms below, far from where it entered.
Below grade is the other path. Soil holds water against foundation walls after every rain. It wicks up through the masonry by capillary pull. Basements smell damp. Paint bubbles on inside walls. The source is outside, feet below the lawn, and inside paint never fixes it.
Waterproofing starts by finding the path. We read the stains like a map. We test the joints for softness. We look at caps, sills, and flashing lines. Treating the wall without finding the entry is painting over a leak. We find it first, then we treat it.
Breathable sealers, not plastic coats
Masonry must breathe. Water vapor moves through brick and mortar all the time, in and out with the weather. A good sealer lets vapor escape while blocking liquid water from getting in. That one-way street is the whole trick, and it is what separates good waterproofing from harm.
Penetrating sealers do this well. They soak into the pores and line them, invisible. Water beads on the surface instead of soaking in. Vapor still escapes freely. The wall stays dry without being sealed shut. From the curb, nothing looks different at all.
Film-forming coatings fail old walls. They paint a plastic skin over the brick. Vapor gets trapped behind it with nowhere to go. In winter, trapped water freezes and pops the brick face clean off. We see spalled walls under failed coatings every year, and the coating always gets the blame it earned.
We use penetrating sealers matched to your masonry. Brick gets one formula. Old lime mortar gets care in the choice, since soft joints drink sealer differently. The wall beads water and breathes free. That is waterproofing that respects the wall instead of fighting it.
Ready when you are. Call (301) 679-9193 or send the form for a free on-site estimate.