Part H · the register

Before Anyone Tears Off That Slate-Look Roof, Test a Piece

Some older roofing that resembles slate is asbestos cement, and the answer affects removal, scheduling and price.

A gray, flat roof tile on an older Kirkwood house may be natural slate. It may also be asbestos cement, a manufactured roofing material used for decades because it resisted fire and lasted longer than many early asphalt products. The two can look similar from the ground. A roofer should not settle the question by looking at a photograph or tapping one tile with a tool. If the material could be asbestos cement, testing a small sample before the contract is signed gives the homeowner the specific fact needed to plan the work.

This is mainly a removal issue. Roofing material that remains intact on the house does not create the same situation as material being broken, cut, dropped and loaded into a container. An ordinary tear-off plan assumes a crew can remove the covering with roofing tools, send debris to a ground tarp or container and clean the property with magnets and hand collection. Suspected asbestos cement changes that plan. It may require a qualified inspector, laboratory identification, different handling and a disposal destination that accepts the material.

Town roofing

Kirkwood has houses from many building periods, and one address can contain several generations of roofing. The main house may have an older tile-like covering while an addition carries asphalt shingles. A porch may have low-slope membrane roofing. A detached garage may have been reroofed years after the house. Do not assume every roof plane contains the same material merely because the colors are close.

Asbestos cement roof pieces are often rigid, relatively thin and formed in repeated rectangles or diamonds. Some have a surface texture intended to resemble slate or wood. Age, shape and appearance can justify testing, but they cannot confirm the content. Natural slate can also vary in thickness and color. Fiber-cement products made without asbestos exist too. The reliable answer comes from an appropriate sample examined by a qualified laboratory.

Sampling should be planned instead of improvised. Breaking a corner off from the eave with pliers is not a useful homeowner test. It can release dust, leave an opening and damage material that may already be brittle from decades of weather. A qualified person can choose a sample location, limit disturbance and close the small opening afterward. Ask for the laboratory report and keep it with the house records.

The condition of the roof still matters while testing is pending. Missing pieces can admit water. Fasteners can loosen. Flashing at a chimney, wall or plumbing penetration can fail even when the field tiles remain serviceable. A temporary measure may be possible, but walking across old rigid tiles can crack more of them. The first inspection should identify a safe access method and separate an active leak from the question of what the roof covering contains.

Kirkwood's freeze thaw cycle makes that distinction important. Water can enter a small crack, freeze, expand and widen it. Ice at an eave can also hold water above the normal drainage path. Neither condition proves the tile contains asbestos, and neither means the entire roof automatically needs replacement. It does mean that repeated patching without identifying the material can create a larger and more expensive removal problem later.

A roof permit and an asbestos assessment answer different questions. Kirkwood has its own municipal permit desk. A roofing contractor should confirm the permit requirements for the proposed roofing work at the address. That municipal step does not identify an unknown roof product. Likewise, a laboratory result does not replace any permit, inspection or construction requirement that applies to the new roof.

What it costs

The first useful cost is the price of getting a defensible answer. Sampling and laboratory analysis add an early expense, but they can prevent an ordinary tear-off price from being mistaken for a complete project price. Get the testing charge, the expected reporting time and the number of samples in writing. Different-looking sections may need separate samples because they may have been installed at different times.

If the result is negative, the roofing proposal can proceed using the removal assumptions stated in the bid. The contractor should still describe the number of layers, the roof area, access, protection for landscaping, disposal and the rate for deck repairs discovered after removal. Older Kirkwood houses may have board decking instead of modern sheet decking. That is a separate condition and should have its own written allowance or unit price.

If the result confirms asbestos, the original tear-off number should not simply receive an unexplained surcharge. Ask for a revised scope that identifies who will remove the material, how it will be handled, where it will go and which work belongs to the roofing crew. The contractor performing the new roof and the party handling regulated material may not be the same company. The paperwork should make each responsibility clear.

Several details can change the removal price:

• The amount of confirmed material and whether it covers the whole house or only one section.
• The roof pitch, height and number of separate roof planes.
• Whether tiles can be removed intact or are already badly broken.
• Access for containers, workers and material handling equipment.
• Protection needed for porches, gardens, neighboring property and narrow side yards.
• The accepted packaging, transportation and disposal method.
• Decking or flashing repairs that begin only after the old covering is removed.

A low number based on ordinary shingle disposal is not comparable with a number that includes specialized removal. Put the scopes beside each other and mark every responsibility that appears in one but not the other. If a line says only "disposal included," ask what material the bidder assumed would be disposed of.

The replacement roof is another decision. Keys Roofing installs Atlas and Malarkey shingles, but shingles cannot simply be fastened over every old roof assembly. The deck has to be exposed or otherwise evaluated as the approved assembly requires. The written proposal should identify the planned underlayment, flashing, ventilation, starter material, field shingle and ridge cap. It should also explain what happens if the exposed boards have gaps, rot or inadequate fastening.

Repair economics can point in a different direction from replacement economics. A sound natural slate roof may justify work by a slate specialist. An asbestos cement roof with a few damaged pieces presents a different problem because matching replacement pieces may be scarce and disturbing adjacent brittle pieces can enlarge the repair. An old three-tab asphalt section may have aged beyond a sensible isolated repair even if the tile section remains serviceable. Each roof area should be judged by its own material, condition and remaining repair options.

What to ask

Start with one direct question: "What evidence supports your identification of this roof material?" A useful answer distinguishes observation from confirmation. It may say that the shape and age create a reason to test, but only the report will establish the content. Be cautious if someone declares the roof asbestos-free from the driveway or calls it asbestos solely because it looks old.

Before authorizing sampling or removal, ask:

1. Which roof sections appear to contain the same material?
2. Who will collect the sample, and how will the sample point be sealed?
3. Which laboratory will issue the result?
4. Will I receive the full written report?
5. Does the quoted roofing price assume a negative result?
6. If the result is positive, who prepares the revised removal scope?
7. Who is responsible for transportation and accepted disposal?
8. How will broken pieces and dust be kept out of soil, gutters and neighboring property?
9. What work can begin before the result, and what work must wait?
10. Who will confirm Kirkwood's permit requirements for the final roofing scope?

Also ask how the house will be kept dry between separate phases of work. Specialized removal may finish before the roofing crew starts installing the new assembly. The contract should state who controls temporary protection during that interval and what happens if rain is forecast. St. Louis weather can move quickly during spring hail season, and an exposed deck should not depend on a vague promise that another crew will arrive soon.

Keep the report, photographs, revised scope, disposal records and permit documents together. Those records tell a future buyer or contractor what was actually found and removed. They also reduce the chance that a garage roof, porch roof or small rear addition will be incorrectly treated as part of the tested area.

Keys Roofing can inspect the roof, photograph its separate sections and prepare a written roofing scope based on what the testing establishes. To discuss access, sampling questions and the replacement work that may follow, call the Kirkwood office number at (314) 220-2333.