Can homes have flat roofs? - Part 2

• Easy to apply, no heat required
• Liquid creates one monolithic, smooth and effective watertight membrane (no seam adhesion required)
• Highly resistant to sun’s UV rays and heat
• Dries rapidly

Disadvantages

• May require finding a specialized contractor experienced with its application

How it’s applied

• A first layer of liquid cold-poured on top of insulation, with a second layer applied on top of reinforcing asphalt or felt

7 - Spray on roofing

Often called liquid roofing, this technology is gaining ground in North America as it becomes more familiar to the industry. Proponents like this product because it’s easy to apply and provides smooth, effective coverage.

Materials

• A sun-reflective protective coating made of silicone, acrylic or aluminum 

Advantages

• Easy to apply
• Creates an effective weatherproof, fire-resistant and UV-reflective barrier
• Because it’s sprayed on, creates a seamless layer

Disadvantages

• Expensive
• May require searching for specialized contractor who is experienced with its application

How it’s applied

• Sprayed directly over insulation

8 - Metal roofing

Metal is an expensive, but stylish option because it is straightforward, unique and non-chemical.

Materials

• Large panels of standing seam steel, aluminum, zinc or copper

Advantages

• Long-lasting
• Easy to install
• Acts as both waterproofing and sun/fire protection for the roof (no top layer required)
• Easy to maintain
• Made of recycled materials (which can again be recycled after use)

Disadvantages

• High cost of materials
• Can be noisy during a rain event.
• Hail can create a great deal of damage to the roof surface.

How it’s applied

• Installed over insulation
• Repaired using soldering (for aluminum, use fiberglass patches or aluminized caulking)

Can you have a flat roof with shingles?

Roofing experts discourage the use of shingles on a flat roof. As few points of sealing as possible will reduce potential for leakage. This is why most flat roofs use large squares or single sheets of materials. In some cases, a homeowner may choose an option such as a Self-Adhering Membrane Residential Roof System, which offers the multi-layer protection of a membrane roof, with the traditional granule look of a shingled or built-up roof. These offer lasting protection against snow, ice and elements – and hold up well to foot traffic on low-slope roofs. They’re peel-and-stick cold application, and availability in single, double or triple layer reinforcement make them a popular choice for roofs with at least 1:12 slope.

How to make a flat roof last

It is incumbent upon the owner of a flat roof to regularly inspect and maintain the roof. This will make a significant difference in maintaining its integrity and longevity. A basic inspection is suggested twice a year and after any major rainstorms. We recommend consulting a roofing professional who is fully versed in rooftop safety techniques and precautions.

Flat roof inspection checklist:

• In normal circumstances, wait until 48 hours after a rainfall to clean and inspect the roof. Any water should have evaporated by this time. If it hasn’t, that’s a sign of a problem with roof drain parts or the drainage system.
• To help see where any water might be collecting, clean any debris from the flat roof surface, including sweeping or gathering fallen leaves or branches and clearing any loose debris or gravel that may block drainage holes.
• Inspect flashings around the chimney and skylights. If the flashing material is cracked or rusty, you will want to have it repaired as soon as possible.
• Inspect the integrity of the top layer of protection (often a gravel or chipped mineral mixture) to ensure it hasn’t dispersed and left a bald patch. This is key to protecting the membrane underneath while also providing sun and fire protection. On a built-up roof, when gravel becomes sparse, the asphalt layer underneath can dry and crack under the sun. This could lead to “alligatoring,” which may eventually cause the layer to leak and fail.
• Check for any damage, puncturing, rips or wrinkling of the membranes. This might be difficult to see if a layer of chipped material or gravel is on top. Regardless of your flat roof design, take time to thoroughly check the surface for flaws.
• Any damage should be repaired immediately to return watertight protection to the roof and prevent further deterioration.
• If the top layer of gravel needs to be replaced or replenished, consult a roofing professional for proper application over the surface of the roofing material.

Original article and photo source: IKO