A New Malarkey Roof May Need Hand Sealing in Cold Weather

A Malarkey shingle can be nailed correctly and still not be fully sealed when the crew leaves. The nails hold the shingle to the deck. A separate factory applied adhesive strip bonds each shingle to the course below it after the roof receives enough radiant heat. On a sunny, warm roof, that bond may form quickly. On a cold, shaded roof in St. Louis, it may take longer or require hand sealing. That distinction matters if your replacement is scheduled between late fall and early spring.

There is no single outdoor temperature at which every shingle seals. Malarkey identifies several variables: roof surface temperature, sunlight, cloud cover, wind, shingle color, roof direction and slope. A dark south facing plane can become warm enough to activate its seal strip while a light colored north facing plane on the same house remains cold. The temperature reported at the airport does not settle the question.

Material and spec

The nail and the seal strip do different jobs

Roofing nails provide the mechanical attachment. They must be placed in the designated nailing area, driven straight and seated flush without cutting into the shingle. The thermal seal strip provides another part of the wind resistance by adhering the lower edge of one course to the course beneath it. More nails do not automatically replace a seal strip that has not activated.

The release tape on the back of a Malarkey shingle is not the seal strip, and it is not supposed to be peeled off. Its purpose is to keep shingles from sticking together in the package. The actual sealant is positioned so it contacts the neighboring course after installation. A proposal that says only how many nails will be used does not answer how an unsealed winter roof will be addressed.

Malarkey says its shingles use a modified SEBS adhesive. That describes the factory adhesive, but it does not mean the adhesive bonds instantly at any temperature. The manufacturer states that sunlight and radiant roof temperature activate the seal. It also states that wind warranties apply only after the shingles are sealed, either by activation of the factory strips or by hand sealing. Failure to seal under adverse conditions is not treated as a manufacturing defect.

What hand sealing means

Hand sealing, sometimes called hand tabbing, means placing measured dabs of compatible asphalt roof cement beneath the shingle and pressing the shingle into the cement. For a Malarkey laminate shingle, the manufacturer calls for four evenly spaced, quarter-size dabs of asphalt roof cement meeting ASTM D4586. The cement should not be spread into a continuous heavy band. Too much can bleed from beneath the shingle or contribute to blistering.

The pattern is different for some specialty products and accessories. Malarkey's Windsor designer shingle calls for a dab beneath each shingle tab. Hip and ridge pieces are sealed beneath their lower corners. The written scope therefore should identify the field shingle and the hip and ridge product instead of using one vague line for all hand sealing.

Hand sealing is required by Malarkey on roof slopes greater than 21:12. The company also strongly recommends it when adverse conditions such as cold weather, high wind or blowing dust may keep the factory strip from activating. A common suburban roof may not approach a 21:12 slope, but dormers, turrets and decorative steep faces sometimes do. Those small sections need to be identified during measurement because their fastening and sealing requirements can differ from the main roof.

Why a St. Louis roof can seal unevenly

St. Louis weather produces mixed conditions on one roof. A January afternoon may warm the south and west planes while the north plane stays shaded. Bare trees can expose part of a roof to sunlight while a chimney or neighboring house shades another part. Wind removes heat from the surface. Light colored shingles generally warm more slowly than dark colors. Steeper shingles press less firmly against the course below, so gravity provides less help while the seal develops.

The freeze thaw cycle is not itself a substitute for sealing. A loose lower edge can remain vulnerable while the roof waits for a sufficiently warm, sunny period. Spring hail season and strong wind fronts can arrive before a winter installation has received much useful heat. That is why the question belongs in the scope before installation, not after someone notices lifted tabs.

Cold also affects handling. Hip and ridge pieces have to bend over a roof peak. Shingles installed through a valley must conform to the valley shape. Malarkey recommends warming cold material enough to keep it flexible and reduce cracking. Bundles should not be bent, dropped or forced into position merely because the crew can still drive a nail through them.

Sealing does not correct an unsuitable roof assembly. Ice damming at the eave is addressed with proper ventilation, insulation and the specified self-adhered membrane beneath the shingles. Hand sealing the exposed tabs does not stop water that has backed up beneath the roof covering. It also does not repair rotten decking, incorrect flashing or a low slope section that should use a different roofing material.

What it costs

Cold weather hand sealing adds labor and roofing cement. The crew has to lift each shingle edge carefully, place the specified amount in the specified locations and press the shingle down without smearing cement onto the exposed surface. On a simple ranch roof, that is one calculation. On a roof with several dormers, hips, steep faces and shaded valleys, it is a different calculation.

The useful price question is not whether hand sealing is free. It is whether the bid already includes it under stated conditions. One contractor may include hand sealing whenever the forecast and roof orientation make natural activation uncertain. Another may price it as an added line. A third may plan to install the roof and wait for warmer weather without explaining who will inspect the seal afterward. Those are different scopes even if every bidder names the same Malarkey shingle.

Ask for a dollar amount or a clear included line before signing. A usable line might identify the affected roof planes, the ASTM D4586 cement, the application pattern and the hip and ridge treatment. Avoid a general allowance called cold weather supplies. It does not tell you whether the field shingles, ridge pieces and steep sections are included.

Scheduling can also change the cost. Moving a project to a warmer period may avoid some hand sealing labor, but waiting is not always sensible if the roof is actively leaking or losing tabs. A roof that can safely wait should be judged by its present condition, not simply its age. An older three tab roof with brittle edges and repeated repairs may no longer be a good candidate for another small repair while the replacement date is postponed.

What to ask

Put these questions to the contractor while the proposal can still be revised:

• Which Malarkey field shingle and which hip and ridge product are included?
• What weather or roof conditions will trigger hand sealing?
• Does the quoted price include hand sealing on the field, hips, ridges and steep faces?
• Will the cement conform to ASTM D4586, and will it be applied in the manufacturer's stated pattern?
• How will cold hip, ridge and valley pieces be warmed or handled to prevent cracking?
• Who checks roof planes that have not received enough sun to activate the factory strip?
• Will photographs of the cold weather details be placed in the job file?

Also ask what happens if the installation day begins warm and turns cold. The answer should be tied to actual roof conditions. A crew should be able to distinguish between shingles that are lying flat, shingles that have bonded and shingles that still need hand sealing. Looking flat from the driveway is not proof that the adhesive has activated.

Do not ask anyone to pry up every shingle after the bond has formed. Testing should be limited and careful because aggressive lifting can break a sound seal. If a follow-up inspection is part of the plan, the scope should state when it occurs, which planes receive attention and what the contractor will do if tabs remain loose.

The proposal should also separate permit administration from the material detail. Municipal permit desks across St. Louis County do not all follow one process, and a permit inspection is not a manufacturer installation audit. The local inspector may check items within the adopted code without verifying every adhesive dab or every factory seal strip. The contractor remains responsible for following the applicable Malarkey installation instructions.

Keys Roofing can identify the Malarkey product, roof planes and cold weather sealing method in a written scope before work begins. Ask for photos of steep faces, shaded planes, hips and ridges with the completion file. To discuss a winter installation in St. Louis or the greater metro area, call (314) 220-2333.