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Basement · Interior Drainage

Dry Basements Start With Interior Waterproofing in Portland

Tight yards, finished landscapes and attached structures often make exterior excavation impossible. Portland Concrete solves wet basements from the inside with perimeter drainage tile, a sump pit and pump system that intercepts groundwater before it crosses the slab. This is a proven alternative to exterior waterproofing when site conditions demand it. Free written estimate on every project.

  • Perimeter drainage tile system
  • Sump pit and pump installation
  • Free written estimate, firm timeline

When outside isn't an option

How Interior Drainage Solves a Wet Basement

Exterior waterproofing requires digging down to the foundation footing on the outside. In many Portland homes, that means removing a deck, cutting through a patio, or excavating under a garage. When the cost or disruption is too high, interior waterproofing becomes the practical answer.

The system works by accepting that groundwater will reach the basement wall, then capturing it before it spreads across the floor. We cut a trench along the interior perimeter, lay drainage tile on a stone bed, slope it to a sump pit, and install a pump that moves water to daylight. The wall is sealed at the slab line so moisture dries inward instead of bleeding outward.

The result is a dry basement floor ready for renovation, storage or finishing. The pump is the only moving part, and a battery backup ensures it runs even if the power goes out during spring snowmelt, a common Portland scenario.

Recent work
interior drainage tile installed in basement perimeter trench
sump pit and pump system in finished Portland basement

Installation sequence

Installing Interior Basement Drainage Step by Step

  1. Assess water entry and sump location

    We identify where water reaches the slab, measure the existing floor depth, confirm the best sump pit location, and verify the discharge path to daylight before cutting any concrete.

  2. Cut and excavate the perimeter

    The basement floor is saw-cut along the wall line, the trench is dug to the correct depth, and any failed or deteriorated drainage is removed so the new system sits on clean material.

  3. Lay tile, set sump, test system

    Drainage tile is placed on a stone base, sloped toward the sump pit at the low point, the pump and discharge line are installed, and the system is tested with water to confirm flow.

  4. Backfill, pour, and seal

    Stone backfill is compacted over the tile, a new concrete slab is poured to lock the system into the floor, and the wall-to-slab joint is sealed so the wall can dry inward without leaking.

Right tool for the job

Interior Waterproofing Solves a Specific Problem

Interior waterproofing is not a replacement for fixing a failing foundation wall or addressing a known exterior cause. If the wall is cracking structurally or if there is a clear external issue that can be reached, exterior waterproofing is still the better choice.

Interior systems excel in established homes where the outside is finished and a recurring leak is making the basement unusable. The slab stays dry, the basement becomes finishable, and the pump is the only maintenance item. Pair it with crack repair if wall cracks are also weeping, and the basement is ready for whatever comes next.

Schedule a basement assessment
completed interior basement waterproofing system in Portland home
Interior Installation location
Pumped out Water destination
Free Written estimate

Common questions

Interior Basement Waterproofing Questions, Answered

Drainage tile, sump pits, pumps and when interior is the right answer to a wet basement.

For its job, yes. The two systems do different work. Exterior keeps water from ever reaching the wall; interior accepts that water reaches the wall, intercepts it at the slab perimeter and pumps it out. When excavating outside is impractical, the interior system is the right one.
An interior system needs a sump pit and a pump to move collected water out. A battery backup pump is strongly recommended in Portland, where spring runoff and power outages can overlap. We size the pump and pit to the inflow we measure.
The perimeter has to be opened up, which means baseboards, lower drywall and any finished flooring against the wall come off in the work zone. We coordinate that carefully so the rest of the basement is undisturbed.
It will intercept the water at the slab so the floor stays dry, but a leaking wall crack itself is a separate fix; pair this with crack repair or, if the crack is structural, foundation crack repair from the engineered side.
A typical residential interior system takes about a week from cut to closed slab, depending on the perimeter length and how much of the basement has to be uncovered to reach the work. The full schedule is in the quote.

Homeowner reviews

What Portland Homeowners Say About Their Interior Waterproofing

★★★★★ 4.9 · 87 reviews on Google
Read all reviews →
★★★★★

We could not dig up the front of the house. Interior system put in, sump pit cut, dry basement two springs running. Honest about the system being the right tool here.

S. F.
Portland
★★★★★

Existing finished basement, leaks in three corners. They opened only what they had to, installed the tile and sump, closed it back up clean. The pump runs, basement is dry.

E. I.
Vancouver
★★★★★

They explained why interior was the answer in our situation and not just upselling exterior. The system has worked through every melt since. Trust earned.

Q. P.
Hillsboro
★★★★★

Battery backup pump was their recommendation and we are glad we listened. Lost power for a day this spring; basement stayed dry the whole time. Worth every dollar.

X. B.
Gresham

Next step

Get Your Free Interior Waterproofing Estimate

Describe where water enters your basement, how often it happens, and what is finished around the perimeter. We will visit free, assess the conditions, and send a written quote with a firm timeline within one business day.

Free on-site assessment and written quote within one business day.