I have finally confirmed that it s allowed in ontario provided the plan passes the building inspector.
New roof over existing roof.
How to install a roof over an existing roof determine the feasibility.
The new roof will be a metal roof.
The method of installation varies wildly.
Installing a new roof over an existing one can only be done if you have shingles because you can only put shingles over shingles.
The condition of the existing roof is critical.
The cheapest option would be to leave the old roof in place and place the new rafters over the existing roof.
Many arizona homeowners with shingle roofs do decide to roof over their existing shingles because.
Shingles that are raised or misshapen make it hard to lay a smooth flat layer of new shingles on top.
Use premade roof trusses premade roofing trusses will be easier and take less time than installing a stick built roof.
Another reason is curling shingles as you can only install a new layer if the first one is completely flat and level.
We are doing all the work ourselves so tearing off the old roof would be a real problem.
Once your roof is back in tip top condition you can start looking at the various roof over options.
Inspect the condition of your current roof.
Premade trusses will form the skeleton of your new roof above your old roof.
Why installing new shingles over old shingles can be good.
When you should tear off your roof and start from scratch instead.
Multiple layers of shingles can make it difficult or impossible for the nails to penetrate.
What you need power nailer or roofing hatchet tape measure roofing shovel or flat pry bar hammer drill carpenter s square straight cut tin snips utility knife chalkline broom.
Use the guide we.
We do not want to remove the existing roof so we are proposing to build directly over the old roof.
The roof should be in sound.
You can save money because there s no dump fee for removing your old roofing and there s no need for additional felt paper over the old roof.
Let s start with the good.
That s also why building codes commonly limit re roofing to no more than two layers.
Your house will probably be worth less.
When roofing over your existing shingles can be a good idea.
Installing new roof shingles over old effectively doubles the weight of the roofing so you have to make sure your roof structure can handle the extra load.
It is not possible to mix materials nor to install a new layer over slate or wood tiles.