Frequently Asked Questions

How often should I be inspecting my roof and how much should this cost?

You should retain a qualified roofing professional (roof consultant or roofing contractor) to inspect your roof at least twice a year (spring and fall are best). You may also require an inspection after major weather events and/or in the case of suspected roof damage. The inspector should ensure that all roof drains are working and free of debris, and should also inspect the overall roof condition and roofing details. Your roofer or consultant can prepare a bi-annual inspection check list suited to your application. Costs will vary depending on the location, type and size of building, but generally this should be in the range of $ 250.00 - $ 750.00, plus applicable taxes.

How should I decide whether to continue to repair my roof or replace it?

Generally speaking, if you have wet areas in the roof system scattered over the complete roof section and the value of the wet insulation is greater than 25% of the total roof area then your choice should be to replace this roof. Also, if you only have one wet area in a concentrated area greater than 30% of the total roof area, you should consider replacing the roof. Above all the age of the roof and general conditions of the roof flashing and membrane system should be considered in the replacement decision. Other considerations include your short and long term plans for the building, costs, existing water inflow, building use(s), tenants concerns, building contents, potential presence of materials such as phenolic insulation (see below) or asbestos.

How does a roof consultant/contractor decide on the type of roof to be constructed?

There are many factors involved in the decision process for the type of roof construction. Some of these factors include but are not limited to the following: financial constraints, life expectancy, warranties, environment, roof traffic, building height, roof access, existing problems, drainage, existing roof construction and reuse of good materials, construction constraints, access for construction, type of deck, R value of insulation, building codes, qualification of trades in area, building use(s), tenants concerns, aesthetics and building contents.

I have heard that phenolic insulation can corrode my deck. How do I know if I have aproblem and do I have to replace this roof now?

Phenolic insulation is no longer used in the roofing industry as an insulating product. When Phenolic insulation becomes wet a reaction occurs that generates an acid which can corrode galvanized and non galvanized steel decks. However, this product is not a problem with concrete or wood decks, or where gypsum boards have been installed over the deck and sealed with a vapour barrier. If you are unsure whether you have phenolic insulation, contact Maritime Group Corp. to schedule a core cut verification. We suggest that phenolic insulated roofs be scanned (with infrared thermography) at least once every two years. If the roof is dry then there is no need to replace your roof at this time, however regular inspection, maintenance is required to prevent the insulation becoming wet. With regular inspections phenolic-containing roof systems can be monitored for replacement before water infiltration and structural damage occurs.

How critical is drainage to maintaining my roof over the long term? How expensive is it to add more drains if I need them?

Good drainage is critical in maintaining a long-lasting roof. You should have at least one roof drain for every 3 - 4,000 sq. ft. of roof area. A general rule is the roof should be dry 48 hours after a rainfall to have good drainage. Drains can be added for about $600.00 - $1,000.00 each, including plumbing, depending on access, interior conditions, and the type and location of existing roof drains.

I have ice dams building up at the eaves of my (residential house) roof. What causes this?

The key to any good steep slope roof system is ventilation. Building codes require 1 sq. ft. of ventilation for every 300 sq. ft. of ceiling space. The ice build up is caused by poor ventilation of the attic space, as warm (interior) air tries to escape at the edges of the roof and meets with cold moist air. If you only have one or two attic vents then you may require additional ventilation to improve air flow in the attic. This can usually be accomplished by installing additional vents at the ridge and eaves and/or a rotating vent system. Please contact our office for more information. Our team of roofing professionals will be pleased to assist you with all your roofing requirements.

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