roof replacement
#1
01-15-08, 12:09 PM
roof replacement
I'm planning to redo the roof because the layer is about 20 yrs old. Can I put the new shingle over the old one? Condition is still okay on the old shingle. also, what are the advantages and disadvantages of putting two layer of shingles? thanks in advance
#2
01-15-08, 12:41 PM
Super Moderator
roof
You'll hear a lot very soon, but I got here first.
Yes you can shingle over, but should you?
Pro:
No ripoff required, therefore less to haul off
uhhhh...thats all I can think of.
Con:
Additional weight on the roof
Decreased lifespan of new roof due to additional heat retention
No chance to inspect sheathing and underlay for damage/correct initial install
Need for longer fasteners to ensure penetration to sheathing
Appearance on edges
That said, if the old roof is still good per your post, why are you replacing it?
JMO
Yes you can shingle over, but should you?
Pro:
No ripoff required, therefore less to haul off
uhhhh...thats all I can think of.
Con:
Additional weight on the roof
Decreased lifespan of new roof due to additional heat retention
No chance to inspect sheathing and underlay for damage/correct initial install
Need for longer fasteners to ensure penetration to sheathing
Appearance on edges
That said, if the old roof is still good per your post, why are you replacing it?
JMO
#5
01-16-08, 07:46 AM
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As a practical matter the biggest problem I find at “re-roofs” during home inspections here in Chicago is that roofers often do not bother to properly install and/or re-install flashings at roof penetrations and at junctions with other surfaces such as dormers and chimneys.
Since on composition shingle roofs it's flashing defects than deteriorated roof coverings which are the usual cause of “roof leaks", a re-roof often provides far less than the value of the “new roof" the homeowner paid for.
Since on composition shingle roofs it's flashing defects than deteriorated roof coverings which are the usual cause of “roof leaks", a re-roof often provides far less than the value of the “new roof" the homeowner paid for.
#6
01-17-08, 11:25 AM
Ditto from me also. Some premium dimensional shingles require a complete tear off of the old roof to qualify for warranty and provide maximum hail protection.
I just did the roof on my 47 year old house this summer. The top layer was still good, but the two layers beneath it (yes, two reroofs!) were crumbling and not providing the proper support at the edges for the top layer, giving me problems that required a reroof.
I just did the roof on my 47 year old house this summer. The top layer was still good, but the two layers beneath it (yes, two reroofs!) were crumbling and not providing the proper support at the edges for the top layer, giving me problems that required a reroof.
