Shingles

[Jeff1646]

Just wondering how many layers of shingles you should have on your roof until you have to take them all down. My roof looks like it might need to be redone soon and it already has two layers on it. Also if anyone has any tips of how to put shingles up that would be helpful cause I have never done it before. Thanks

[pushkins]

Your at the max. now. Code states that you are allowed two layers and no more. In the south we never put shingles over old shingles the roofs are cleaned down to ply?OSB re felted and new shingles applied, much of the reason is because of sweating between layers of shingles.

It's not typically hard job to do, but there are quite a few steps that are very important to follow.
1. Make sure you remove everything off the ply/OSB sheathing, all old felt and especially all old nails, don't hammer them in.
2. Lay the felt starting at the eaves and roll across the roof, the second layer should overlap the first by at least 6" (if your in a snow area or have a low slope roof overlap by 12"). Snow areas will require ice dam stop roof covering instead of felt on the first row.
3. Use a chalk line to line the roof across the roof so the shingles will follow the same line and be nice and straight, repeat this every row or every couple of rows if your confident.
4. FOLLOW the manufacturers installation instructions...this is paramount especially in the nailing pattern, Nailing is not just whack in the nails, it is the single most important part to installing shingles. DO
NOT over drive nails, the nail head should be nice and firm on top of the shingle, it should not break the shingle surface.


A tool that will make your life much easier....a shingle remover kinda looks like either a pitch fork or a flat shovel depending on the model.

Hope this helps.

[mrcaptainbob]

Shingle tools....

Amen to all that! Not to mention an air nailer! A small investment to make a difficult job very, VERY much faster.

[pushkins]

Amen to all that! Not to mention an air nailer! A small investment to make a difficult job very, VERY much faster.

Agreed, reason why I didn't mention the nailer was that many insurance companies are getting tough on air nailed shingles, the pressure increase or decrease as the tank fills or empties can lead to nails either being over driven or under driven, this gives concern to the insurance people (and a way out on a claim). So just be careful with monitoring the pressure, drive depths and use a big enough tank.

[mrcaptainbob]

Air nailer...

Interesting point. Thanks for sharing. I did notice that happened when I used my smaller 11 G tank. Even though it ranged from 70/90 psi. The larger tank was far more stable, but I kept it closer to 90.

[HayZee518]

compressor

on an air compressor with a storage tank, the pressure switch has a proportional band within which it operates. the regulator varies the outgoing pressure. if your cutout pressure is 125 psi, the switch will open at or near 125 psi. pressure needs to drop 20 pounds before the pressure switch closes and restarts the compressor motor.
if you have a smaller tank, the on-off periods will be shorter and it will be longer if a larger tank is used. My compressor has a 40 gallon storage capacity and it only starts to re-pressurize if the internal pressure drops 20 pounds. this plus the fact that my compressor has an unloader valve.
the regulator operates off atmospheric pressure and an equalizer spring, which being mechanical weakens over time. if you were to use a precision pressure regulator would probably regulate more accurately.