The purlins are screwed or nailed down to the roof deck depending on how the metal roofing manufacturer has testing for their roofing panels and then the metal is installed to the purlins.
Putting tin roof over shingles.
Another added benefit is that the layers of your old roof will further insulate your home.
Some people think that they can just install the metal roofing right over the old shingles roof without any barrier in between but this is highly not recommended.
Attach them to your roof with 3 inch wood screws in each corner.
The low weight of metal roofing is one thing that encourages this.
The second way to install a metal roof over a shingle roof is with the use of purlins or battens.
This is the minimum that needs to be done.
Steel shingles weigh about 1 4 what asphalt shingles weigh and aluminum shingles weigh about 1 8 what standard shingles weigh.
Move from bottom to top.
Can i install a new metal roof over shingles.
The metal used for the roof can be tin copper aluminum or steel.
On has the metal expands and contracts due to weather changes the metal will actually move.
The main benefit of doing it this way is that it is the fastest way to install a new metal roof over a shingle roof.
However you ll want to check with your local building department before you make any decisions.
Building officials in some areas will only allow a re roof over one layer of shingles while officials in other places may allow you to place the roof over two layers of shingles.
But now that i said that i would tell you that if it was my house i probably would and the reason is i don t want to have all those old shingles under the roof.
This method has its benefits as well.
In terms of performance many homeowners choose a steel roof making it the most popular option when it comes to creating a metal roof over existing shingles.
You will need to lay some 1 by 4 inch pine boards lengthwise every two feet on your roof.
Yes you can and by doing so you save in the labor and hassle of tearing off the old roof and you won t be contributing to filling our landfills.
Yes you can install a metal roof over shingles.
When choosing to install a metal roof homeowners need to take into account several trade offs involving cost and performance.
Well that s why the metal roof is such like an eco friendly product because you don t have to get rid of all of that stuff to the landfills.
The vast majority of installations of the metal roofing systems produced by my company are over existing shingles.