Damp proof course injection typically costs $1,000-$2,500 for a modest home project, with small jobs starting near $500 and extensive work reaching $5,000 or more. The damp proof course injection cost depends mainly on treated wall length, masonry type, access, diagnosis, and local labor rates; it is usually priced per linear foot.
| Item | Low | Average | High | Notes |
|---|---|---|---|---|
| Chemical injection, installed | $8/linear ft | $15/linear ft | $30/linear ft | Rates vary with wall thickness and access |
| Small treatment job | $500 | $1,200 | $2,500 | Often subject to a contractor minimum |
| Whole-home treatment | $1,500 | $3,000 | $6,000 | Assumes roughly 100-200 linear ft |
| Inspection and moisture testing | $0 | $150 | $400 | May be credited toward the work |
What injection costs for a typical masonry home
Contractors commonly quote chemical damp proofing by the linear foot of wall treated. A straightforward job on an accessible brick or block wall may run $8-$15 per linear foot. Dense masonry, thick walls, difficult drilling, or work in a high-cost metro area can bring the rate to $20-$30 per linear foot.
A typical 100-150-foot treatment often totals $1,200-$3,000 before substantial plaster replacement or exterior drainage work. For example, treating 120 linear feet at $15 per foot is $1,800; diagnosis, preparation, and finish repairs can add several hundred dollars. Some companies set a minimum charge of $500-$1,000, so a short wall may cost more per foot.
These figures describe injection into mortar joints or masonry to create a moisture-resistant barrier, not a complete basement waterproofing system. The quote may assume drilling, injecting cream or liquid, and sealing the holes. It may exclude removal of damaged plaster, skirting boards, contaminated materials, exterior excavation, and repainting.
Assumptions: U.S. contractor pricing, accessible masonry, standard injection material, and no major structural repair.
How drilling, chemicals, and wall repairs appear in quotes
A useful estimate separates the treatment from related work. The injection charge is only one part of the bill when damp plaster must be removed or the source of moisture is outside the wall. Compare the listed scope, not just the contractor’s per-foot rate.
| Quote item | Typical price | Common pricing basis | What it covers |
|---|---|---|---|
| Inspection and moisture diagnosis | $0-$400 | Per visit | Moisture readings and initial assessment |
| Drilling and chemical injection | $8-$30 | Per linear ft | Hole drilling, product, and injection labor |
| Plaster removal and replastering | $5-$15 | Per sq ft | Limited interior finish work |
| Skirting or trim removal and refitting | $3-$10 | Per linear ft | Basic removal and replacement labor |
| Waste removal and site protection | $100-$500 | Per job | Debris handling and protection of work area |
| Exterior drainage correction | $500-$5,000+ | Per project | Grading, drainage, or localized excavation |
Separate the injection price from plaster, disposal, and water-management work to avoid comparing incomplete bids. A low per-foot quote may omit preparation, finish restoration, or a written warranty. Conversely, a higher quote may include those tasks, so the total scope matters more than the headline rate.
Ask whether the contractor treats both sides of an internal partition, how corners and wall junctions are handled, and whether the rate includes drilling through paint or render. Confirm how many linear feet are measured and whether the minimum fee applies. A written proposal should identify the injection product, spacing, depth, and any excluded repairs.
Wall thickness and moisture source change the injection rate
Wall construction is one of the strongest price drivers. A single-skin masonry wall may need fewer materials and less drilling than a 12-inch or thicker solid wall. Cavity walls, stone rubble, and walls with irregular joints can require a different approach, additional holes, or specialist assessment. Those conditions can push a standard $8-$15 rate toward $20-$30 per foot.
The measured length and depth of the treated wall matter more than the home’s listed square footage. A 60-foot affected section is not priced like 180 feet of perimeter, even if the homes have similar floor areas. Corners, changes in level, internal walls, and inaccessible sections can increase setup time or complicate the treatment line.
Diagnosis also matters because injection only addresses moisture moving through masonry in a way the treatment can interrupt. Leaking plumbing, roof runoff, high exterior soil, condensation, and water entering below grade can produce similar symptoms. If the contractor finds active leaks or water pressure, repairs may need to come first, adding $300-$5,000 or more depending on the cause.
Finish layers can affect the work. Dense render, tile, or plaster may need removal to reach the masonry, while a damp-proof treatment may require compatible replastering afterward. If damage extends more than 3 feet above the floor or across several rooms, interior restoration can rival the injection bill. Request separate quantities for treatment and finishes.
How many labor hours does a 100-foot treatment take
A small, clear-access job may take one or two workers 4-8 hours. Treating 100-150 linear feet generally takes a crew of two about one to two workdays, depending on drilling conditions, wall thickness, furniture, and cleanup. A complex stone or multi-level property can take longer and may require additional visits.
Where contractors show labor separately, a common U.S. trade rate is approximately $50-$100 per hour per worker, though specialized waterproofing crews and major cities may exceed that range. Some firms bundle labor, equipment, and chemical into a single linear-foot price instead of itemizing hours.
Ask whether the quoted rate includes setup, drilling, injection, cleanup, and return visits. A crew might complete injection in a day but return after drying time to replaster. This does not necessarily mean the injection itself is slow; drying and finish work follow a separate schedule. Moving stored items and clearing access can reduce paid setup time.
Regional pricing from rural homes to major metros
Labor availability and travel distances create meaningful regional variation. Rural markets may have lower hourly rates but fewer specialist firms, longer travel charges, or minimum fees. Large coastal metros often charge more for labor, insurance, parking, and disposal. The ranges below are broad comparisons against a typical national quote, not guaranteed local prices.
| Market type | Typical adjustment | Example installed rate | Why it differs |
|---|---|---|---|
| Rural or small town | 10%-20% below average | $7-$14/linear ft | Lower labor rates; travel or minimum fees may apply |
| Mid-sized metro or suburb | Near average | $10-$20/linear ft | More contractor competition and standard access |
| High-cost coastal metro | 15%-35% above average | $14-$30/linear ft | Higher wages, overhead, parking, and disposal |
Two quotes for the same wall can differ by hundreds of dollars when travel, minimum charges, and finish work are treated differently. Compare at least two local estimates and make sure each bidder measures the same wall length and includes the same preparation. For a remote property, ask whether a travel fee is separate from the treatment rate.
Prices can also vary within a metro area according to access. Narrow alleys, occupied rooms, parking restrictions, or limited work hours may add setup or disposal expense. A contractor working on several walls in one visit may spread mobilization costs across more footage, but the treatment should still be limited to areas supported by the diagnosis.
Three sample quotes for different wall lengths
These examples illustrate how measured footage and scope affect a quote. They assume ordinary access and standard masonry, and exclude major exterior excavation or widespread finish replacement. Local estimates can fall outside these amounts.
| Scenario | Scope and rate | Added work | Estimated total |
|---|---|---|---|
| Short interior wall | 45 ft at $18/ft = $810 | $250 minimum/diagnostic allowance | $1,060 |
| Single-story home | 120 ft at $15/ft = $1,800 | $600 limited plaster repair | $2,400 |
| Thick masonry perimeter | 180 ft at $24/ft = $4,320 | $900 access and finish allowance | $5,220 |
The same linear-foot total can produce a different bill when wall thickness and restoration scope change. In the first example, a minimum charge raises the effective rate above the advertised $18 per foot. In the third, the higher treatment rate reflects a more difficult wall, and the finish allowance covers only limited repairs rather than a full-room renovation.
When reviewing a quote, check for a measured drawing or written footage total, the number of treated walls, and the assumptions behind the rate. If a contractor proposes treating every ground-floor wall, ask which symptoms and moisture readings support that scope. A smaller targeted project may be appropriate, but only if it addresses the diagnosed source and barrier line.
Injection versus drainage or plaster replacement
Injection is not a substitute for every moisture repair. If water is coming through a crack, a local crack repair may cost $300-$1,500. Correcting downspout discharge or grading can cost about $150-$1,500, while a French drain or larger exterior drainage project may cost $2,000-$10,000 or more. These options address different sources and should not be compared as interchangeable treatments.
Do not pay for a chemical barrier until the moisture source has been identified. Replacing plaster alone may cost $5-$15 per square foot for limited work but will not prevent renewed damage if moisture continues entering the wall. A diagnosis that points to condensation may call for ventilation or insulation changes rather than injection; localized ventilation work can range from a few hundred dollars to several thousand.
Ask the estimator to explain why injection is suitable for the specific wall and what happens if moisture persists. A warranty may cover the treated barrier but exclude plumbing leaks, floodwater, rising groundwater, or unrelated wall defects. Read coverage length, transferability, and remedy terms, and ask whether future replastering is included or billed separately.
Reduce the bill by limiting footage and finish upgrades
Begin with a moisture assessment that distinguishes ground-related moisture from leaks, condensation, and exterior water entry. Treating only verified affected walls can avoid unnecessary footage. However, stopping at an arbitrary point may leave a moisture path untreated, so scope reductions should be approved by the professional who has inspected the masonry.
Control the measurable scope before negotiating the per-foot rate. Get bids using the same wall lengths, treatment line, drilling method, product, and finish exclusions. Ask each company to identify minimum charges and separate optional replastering from required injection. This makes a $15-per-foot proposal comparable with one priced at $20 per foot only if the included work is equivalent.
Move furniture, remove fragile items, and clear stored belongings before the crew arrives if the contractor permits it. This can reduce setup and protection time, particularly in basements and narrow utility rooms. Confirm whether homeowners may remove baseboards or plaster; self-preparation can create extra charges if it damages masonry or leaves unsafe debris, so agree on responsibilities in writing.
Keep material choices functional. A premium chemical, extended warranty, or full-room replaster may be justified in some conditions, but ask for the price difference and specific benefit. Bundle related treatment on adjoining walls when the diagnosis supports it, which can reduce repeat mobilization charges. Avoid paying for a broad waterproofing package when the quote does not identify the water source or itemize the work.
Assumptions: savings depend on contractor rules, access, actual moisture source, and whether the proposed scope remains technically sound.