GAF vs. CertainTeed

Match the product tier before comparing

Start with GAF Timberline HDZ and CertainTeed Landmark as named architectural shingle options. Include Landmark PRO if its appearance interests you, but ask what changes in both product and price. For a Class 4 comparison, evaluate GAF Timberline AS II or UHDZ with UltraMat against Landmark ClimateFlex. The company name alone does not identify the specification of your proposed roof.

Have the contractor show the current product sheet for every alternative. Ask whether the exact color and matching accessories can be sourced locally. If the proposal permits substitutions, agree in advance that changes require your approval and updated warranty information.

See the roof as part of the exterior

Your roof's appearance depends on its profile, color variation, slope, and relationship to the siding and trim. Compare samples from the actual product lines being offered. A photograph of another Landmark or Timberline product is useful inspiration, but it may not represent the roof in your estimate.

For a Seattle home, look at the samples outdoors in the light conditions you regularly experience. Ask to see completed roofs with comparable exterior colors if available. Consider ridge and accessory colors too; a field-shingle sample does not show every visible part of the final assembly.

Compare the construction scope line by line

Ask both bidders to describe removal of the old roof, protection of the property, disposal, decking inspection, and allowances for concealed damage. Continue through underlayment, leak protection, starter, edge metal, ridge materials, ventilation, and flashing. The estimate should also address skylights, chimneys, and any roof-to-wall transitions.

A product feature cannot tell you whether the proposed ventilation plan suits your attic or whether a low-slope addition needs a different covering. Ask for a property-specific explanation and keep it with the contract. Agree on who authorizes unexpected repairs and how their cost will be documented before the work begins.

• Use the same measured roof area when comparing totals.
• Keep product upgrades separate from required construction work.
• Ask for the same flashing and ventilation scope in both alternatives.

Read the warranty you are actually buying

GAF's enhanced warranty options and CertainTeed's SureStart PLUS options have eligibility conditions. They should be evaluated as specific packages, with the required accessories, current contractor credentials, and registration process identified. Product defects, installation errors, algae, and wind are separate coverage questions.

Ask for current documents rather than relying on an old brochure or a headline wind number. CertainTeed's current product pages and older literature can differ on upgraded wind figures. The warranty applicable to your installed assembly is the document to review. A limited lifetime term should also not be translated into a guaranteed service life.

Decide based on the complete proposal

Ask each installer for a base proposal and separately priced upgrades. If one total is higher, identify whether the difference comes from the shingle, a warranty package, additional flashing, ventilation work, or a different allowance for repairs. A brand-wide premium cannot explain a specific property quote.

Both brands offer products worth evaluating. Choose after reviewing the written scope, appearance, installer experience, service process, and final cost. Keep photographs, product identification, the workmanship agreement, and manufacturer registration together so you have a useful record of the roof installed on your home.