Location
69 Paul Drive
San Rafael CA 94903
Office hours
Mon – Sat 8:00 AM – 6:00 PM
Sun – Closed
Call us Today
415-785-7522
Location
69 Paul Drive
San Rafael CA 94903
Office hours
Mon – Sat 8:00 AM – 6:00 PM
Sun – Closed
Call us Today
415-785-7522
Call us Today
415-785-7522
Professional Waterproofing & Leak Repair San Rafael
San Rafael's Housing Stock Wasn't Built for This Much Water
Our Services
Balcony, Roof Deck & Parking Deck Waterproofing
Flat roofs and decks are common across San Rafael’s older downtown buildings, and most of them were never built with a real drainage plan, just a coating that eventually wore through. Roof waterproofing in San Rafael on these structures usually involves tearing off whatever’s left of the old surface and starting over with a membrane system built for actual foot traffic and standing water, not just weather.
- Full tear-off and torch-down membrane installation on flat roofs, decks, and parking structures
- Sealing at parapet walls, drains, and penetrations where old coatings typically split first
- Re-sloping low spots that have been holding water instead of shedding it
- Membrane repair for sections that are still sound rather than a full replacement everywhere
- Post-installation flood testing before the surface finish goes back down
Concrete Wall & Structural Leak Repairs
A lot of the concrete leak calls we get in San Rafael trace back to older foundation walls poured before modern waterproofing membranes were standard practice. Once soil around the wall gets saturated during a wet winter, that missing barrier turns into a slow, steady leak. Foundation waterproofing in San Rafael on these walls usually means correcting a problem that was baked into the original construction, not just patching storm damage.
- Excavating along the exterior wall to reach the actual point of entry
- Applying a modern waterproof membrane where the original wall has none
- Injecting and sealing active cracks at the structural level
- Installing drainage to keep saturated soil from pressing back against the wall
- Rechecking the interior side after a rain event to confirm the fix held
Retaining Wall & Basement Waterproofing
San Rafael’s hillside lots in areas like Dominican and the streets above downtown depend on retaining walls that were often built decades before current drainage codes existed. Residential waterproofing in San Rafael starts with a straightforward question: is the water coming from behind the wall through hydrostatic pressure, or running along the surface and finding a crack? The answer changes the whole approach.
- Exterior membrane or coating application on retaining and basement walls
- French drain installation to relieve pressure building up behind a wall
- Surface grading corrections so runoff moves away from the structure
- Sealing at cracks, cold joints, and wall-to-footing transitions
- Sump pump installation on lower-lying lots that need mechanical backup
Our Waterproofing Work in San Rafael
Crawl Space Waterproofing, Gerstle Park
A Craftsman home near Gerstle Park had standing water collecting under the house after heavy rain, soaking into the original foundation walls. We installed a vapor barrier and perimeter drainage system to keep the crawl space dry through the rest of the winter.
Parking Structure Membrane Replacement, Fourth Street
A commercial building along Fourth Street had a parking deck membrane that had cracked and separated at the seams after decades of vehicle traffic. We removed the failed membrane and installed a new torch-down system with re-sloped drainage toward the existing drains.
Slab Foundation Moisture Correction, Terra Linda
A ranch-style home on a slab foundation kept showing moisture along the base of interior walls after storms. Grading around the house was pushing water toward the foundation instead of away from it, so we corrected the slope and added an exterior drainage line.
Why Choose I Construction?
Flood Exposure Varies Block by Block
The Canal District, parts of downtown near A Street, and low-lying sections along the Gallinas Creek watershed carry real flood exposure during atmospheric river storms. A few blocks uphill in Terra Linda or Dominican, the risk profile is almost entirely different. Knowing which category a property falls into changes the whole waterproofing plan before work even starts.
Older Construction Means Original Defects, Not Just Wear
A lot of San Rafael’s housing stock, especially in Gerstle Park and Forbes, predates the waterproofing membranes and drainage codes that are standard today. That means some of what looks like storm damage is really a water leak repair issue in San Rafael that’s been waiting to happen since the wall was first poured, not something that just started this winter.
City and Watershed Permitting
Excavation, drainage work, or anything near San Rafael Creek, Gallinas Creek, or the tidal canal system can trigger separate permitting through the city or the county flood control zones that cover those watersheds. We factor that into the timeline before a project starts, not after a permit office sends it back.
Have a Leak That Needs Attention?
A wall that’s damp after every storm, a roof deck that’s started sagging, or water showing up somewhere it never did before is worth a call now rather than after the next atmospheric river comes through. If you’re already looking into leak repair in San Rafael, homeowners turn to us once a problem shows up; send us photos of what you’re seeing, and we’ll help you figure out what’s actually going on.
Protecting Homes Across San Rafael Neighborhoods
I Construction & Structural Inc. serves San Rafael homeowners with reliable water leak repair and waterproofing solutions tailored to each property.
- Dominican Hills
- Terra Linda
- Bret Harte
- Glenwood
- Santa Venetia
- Sun Valley
- Lucas Valley
- Peacock Gap
- Canal District
- Montecito
- North San Rafael
- Downtown San Rafael
- Marinwood
- Loch Lomond
Frequently Asked Questions
Why does a wall I already patched keep leaking again every winter?
A surface patch usually covers the symptom, not the source. If water is finding its way to that same spot through pressure building up in the soil or a crack that’s still active below the patch, it’s going to come back with the next heavy rain until the actual entry point gets addressed.
Does San Rafael's rainy season change when waterproofing work should happen?
Ideally, repairs happen before the wet months start, since that gives materials time to cure properly and lets us confirm the fix before it’s tested by a real storm. That said, active leaks during the rainy season still get addressed right away, we just plan around weather windows more carefully.
Is a Canal District property more at risk than a hillside home?
The type of risk is different rather than one being simply worse. Canal District properties deal more with rising groundwater and tidal influence, while hillside homes deal more with runoff and hydrostatic pressure against retaining walls. Both need waterproofing, just built around a different cause.
How can I tell a roof deck membrane is starting to fail?
Look for bubbling or blistering in the surface, seams that have started to lift at the edges, or a spot that stays damp long after the rest of the deck has dried. Any one of those usually means water has already gotten underneath the membrane, not just on top of it.
Will waterproofing work disrupt daily use of my property?
It depends on the scope. Sealing and coating work is usually contained to one area and doesn’t affect the rest of the property. Excavation or a full membrane tear-off takes longer and may limit access to that section for a few days, which we’ll walk through before the project starts.
Do older San Rafael homes need a different approach than new construction?
Often, yes. Homes built before modern waterproofing membranes were standard, common in neighborhoods like Gerstle Park and Forbes, sometimes need a full retrofit rather than a repair, since there may not be an existing barrier to repair in the first place.
What happens if a slow leak gets ignored for too long?
It stops being a waterproofing problem and starts being a structural one, wood rot, mold behind finished walls, or soil erosion undermining a foundation. Catching it early is almost always less invasive and less expensive than waiting until it’s visible from the inside.
Can you waterproof a retaining wall without tearing out the landscaping around it?
In a lot of cases, yes, especially if the work can be done from the exposed side of the wall or through targeted excavation. We’ll walk the site first and let you know if anything needs to come out temporarily before we start.
What should I do if a leak only shows up during heavy storms?
Document when it happens and roughly how much water you’re seeing, that pattern tells us a lot before we even get on site. An intermittent leak tied to storm intensity is often about pressure or volume overwhelming a weak point, rather than a constant structural gap.
Get in touch
No Obligation Consultation
No obligation, no pressure, consultation allows you to find out for yourself and decide based on knowledge.
Friendly Crew
We know we are working for you and do our best to make sure you are 100% satisfied with our work.
Safety First
With over two decades of experience we place your safety above all else. All plan and projects take this as first priority.
About us
We are a locally owned and operated company that values honesty and integrity and treats your home as if it were our own. We offer a variety of contracting services customizable to each individual project.
Contact us
I Construction & Structural Inc
69 Paul Drive
San Rafael CA 94903
Office: 415-785-7522
Service: 415-424-5969
Fax: 415-785-7137