| Shiplap was part of new construction during the 70's | | | | the shingles |
| and 80's when plywood hadn't made it into new | | | | I guess the agenda of the shingle companies out |
| construction yet. Being ideal for asphalt shingles in the | | | | there is to eradicate the shiplap deck. Most roofing |
| early days of it's creation shiplap sits beneath the | | | | companies in Vancouver however are ignoring this |
| roof of any home about thirty years old. Shiplap is | | | | warning and continuing to roof without laying down |
| now considered the enemy of asphalt and most | | | | plywood. Most roofing contractors ignore this |
| manufacturers will not warranty a roof that is sitting | | | | because for the average home owner the odds are |
| directly on shiplap. | | | | that they will be fine. Most shiplap out there that |
| Shiplap that has a width of six to eight inches is the | | | | causes a roof failure is weak shiplap and has gaps |
| most ideal and tends to move the least. Moving | | | | between the shiplap boards that cause trouble. |
| shiplap is why there is a problem laying shingles | | | | If you have a concern about your shiplap the best |
| directly above them. In the winter and summer | | | | thing to do is climb into he attic and first measure |
| seasons all shiplap expands and contracts, some | | | | your shiplap. If the boards are wider in width than 8 |
| more than other and as a result the shingles move | | | | inches or narrower than 6 inches than you should get |
| when they were not designed to move. Interlock | | | | plywood. If you can see gaps in your shiplap |
| shingle were ideal for shiplap and covering cedar | | | | between the boards then get a plywood deck. The |
| shake, unfortunately in British Columbia Interlock | | | | rest of you I really wouldn't bother. In Vancouver a |
| shingles are no longer available which means | | | | 30 year old home is generally a tear down. |
| technically everyone should be getting plywood laid | | | | One more note when it comes to shiplap is that if |
| down over the shiplap in order to stopped the shiplap | | | | you have a gable or rake style roof and need the |
| from moving. Even if the shiplap does move with | | | | barge boards replaced make sure you get a excellent |
| plywood on top there will be minimal movement of | | | | carpenter who has experience with shiplap. |