At roof intersection level the original outer skin of the existing property becomes an inside wall.
Joining extension roof to existing wall.
Often with new construction the roof flashing is first nailed to the wall.
A lean to roof also called a shed roof slopes in one direction with rafters that rest against another structure at their high end and overhang.
When an existing house is constructed with cavity walls extending the building should always follow the parallel rule the term applied to both skins maintaining an equal distance apart it is also important to consider how the existing house walls will interface with the new walls.
I live on the top floor of an ex council flat built in the 50s.
Then the house wrap and exterior wall covering are installed over this roof flashing.
In the case of a flat roof extension the height of the highest point of the roof must not exceed the parapet or eaves of the existing roof.
The junction of the new walls to the existing walls should ensure that dampness cannot track back into the new home or the existing home.
Proper roof wall abutment flashing examples.
If the rear wall of the existing house has a gable then the new walls of the extension must not exceed the height of the rear existing wall excluding any gable being built as part of your extension.
There sometimes is a problem with movement differences of the wall and the roof decking when the flashing is fastened to both the wall and the roof.
We have an extension being built and the brick layer used mortar to join the new wall to existing below floor level and furfix.
An effective horizontal damp proof course dpc should be present in the existing wall which must be linked to the new dpcs and damp proof membrane dpm of the new home.
New cavity wall joined to existing rendered wall using furfix wall starter.
Below are two photographs of roof wall step flashing completed and effective of a slate roof against a brick wall below left and in process with step flashing against a dormer sidewall before the dormer siding has been put in place below right.
How to tie a additions roof to existing roof roof additions to existing roofs how to construct a roof from an exsisting shead how to change a roof line how to attach a deck roof to existing roof how to add a roof over porch attache porch roof on house attach shed roof to house adding a roof to screened in porch adding a roof to existing.
To do this we had to extend the plane of the shed roof out over the porch roof creating a small triangular extension of the existing roof.
How to join a lean to roof to an existing roof.
If the extension is built on your land then normally a party wall agreement should have been set up already and that means you don t need to build a new wall along that wall.
I hope you can help.