Roofing: How to Strengthen Existing Roofs

A strong roof will help keep wind and water out during high wind events.

If your roof is relatively new and in good condition, this option will help strengthen it and meet the IBHS FORTIFIED criteria for sealed roof deck.

A closed cell polyurethane spray foam applied to the underside of the roof deck.

Install a closed cell spray polyurethane foam:

• Spray foam to the underside of the roof deck to enhance the roof sheathing attachment to the roof framing members and provide a sealed roof deck.

• There are some closed cell spray foam adhesives that can be applied in the attic along the joints between the roof sheathing and the rafters or trusses. These adhesives are widely used in the manufactured housing industry and are different from insulating products such as Icynene.

• If also sprayed over the joints between the sheathing, these adhesives can help to keep water out if the roof covering is damaged and can be considered a sealed roof deck.

• These systems use special chemicals that are mixed on site and require professional installation.

• Costs have typically started just under $2 per square foot of roof and go up depending on the difficulty of attic access.

• Make sure you use a closed cell foam that is rated for uplift.

• Choose a qualified professional installer.