{"id":1707,"date":"2022-03-23T05:47:20","date_gmt":"2022-03-23T05:47:20","guid":{"rendered":"https:\/\/whatblueprint.com\/?p=1707"},"modified":"2023-04-14T13:17:37","modified_gmt":"2023-04-14T13:17:37","slug":"can-you-roof-over-wet-plywood","status":"publish","type":"post","link":"https:\/\/whatblueprint.com\/can-you-roof-over-wet-plywood\/","title":{"rendered":"Can You Roof Over Wet Plywood?"},"content":{"rendered":"\n

If you have a noticeable curve to your roofing and are worried about the roof leaking, don\u2019t worry; you\u2019re not alone. We built a wooden cottage a few years ago; the contractor assured us he could do the roofing in rainy weather. He said the plywood would dry out without looking bent; that was not the case; I wondered whether you could roof over wet plywood.<\/p>\n\n\n\n

You should never install a roof over wet plywood or another roof sheathing. The water that is trapped underneath the roofing will heat up. That combined with the roofing weight will cause the wood to swell, bend, warp and cause pits where the steam from the heated water escapes.<\/strong><\/p>\n\n\n\n

After speaking to an expert in roofing, I knew I needed to get the problem fixed before the problem got worse. I contacted our contractor, but he had disappeared. In the end, I had to pay more to get a professional roofer to fix my roof. It was an expensive lesson, so I thought I would share the information I wish I had before having my roof installed over wet plywood.<\/p>\n\n\n\n

Can You Install Roofing Over Wet Plywood?<\/h2>\n\n\n\n

Should you install roofing if you live in an area prone to rain and the plywood is wet? You should never install roofing over plywood. Plywood doesn\u2019t get damaged from water or rain immediately, but it needs to dry out before installing the roofing.<\/p>\n\n\n\n

Keep in mind if the plywood is wet when the roof shingles are installed, the damage the water causes will influence how well the roof holds up and the overall look. The expansion and contraction of the wood when it dries can cause all kinds of problems.<\/p>\n\n\n\n

Regarding roofing code violations, installing roofing over wet plywood is against the roofing code, meaning if your contractor installs the roof over wet plywood, it could lead to fines and insurance issues should something go wrong.<\/p>\n\n\n\n

What Can Happen If You Install Roofing Over Wet Plywood?<\/h2>\n\n\n\n

If you or your contractor are thinking of roofing over wet plywood, you need to take a step back and rethink that decision. Some DIYers and contractors might think it\u2019s ok to roof over wet plywood as it will dry beneath the roof and be fine. However, that is not always the case.<\/p>\n\n\n\n

 The Consequences Of Roofing Over Wet Plywood<\/h3>\n\n\n\n

Here are a few more serious things that can happen if you should roof over wet plywood:<\/p>\n\n\n\n

There Will Be Fastener Issues<\/h4>\n\n\n\n

One of the first signs of trouble if you try roofing over wet plywood is your shingles won\u2019t fasten properly. The water causes wood to swell, warp and bulge. The shingles are fastened with adhesives or roofing nails.<\/p>\n\n\n\n

As the wood expands and retracts, the nails might become loose, and you might get leaks. The adhesives won\u2019t stick as it the manufacturers intended, the roofing will become sticky and slippery, and the roof shingles will slip and fall off or get stuck in a skewed position. <\/strong><\/p>\n\n\n\n

You\u2019re Warranty Will be Void<\/h4>\n\n\n\n

Most manufacturers of roofing materials give warranties on their products, but the warranty might be invalid if the roof was installed improperly. That means if you knowingly install the roofing on wet plywood and it creates a problem with the roofing material, you might lose the warranty.<\/p>\n\n\n\n

It Creates Hazardous Working Conditions<\/h4>\n\n\n\n

Before you install the roof on your home, you should consider speaking to an expert contractor about the best way to move forward should the timing be during the rainy or snow season. If you install roofing and the plywood is wet or has a thin layer of snow or ice, it creates dangerous working conditions.<\/p>\n\n\n\n

The roof could become slippery, especially if there are sheets of ice that have formed on the plywood. Speaking to a contractor will help you decide when the best time would be to install the roofing.  <\/p>\n\n\n\n

It Could Cause Cupping<\/h4>\n\n\n\n

The roofing standard that most contractors use is to set the roof rafters at least 2ft apart, but they install plywood decking with a minimum of 7\/16-inches thickness. A few builders will try to cut costs by installing thinner 5\/16-inch plywood; as a result, the thinner plywood is more likely to cup than the thicker 7\/16-inch.<\/p>\n\n\n\n

It Could Cause Rotting<\/h4>\n\n\n\n

If you install the roofing over wet plywood, it could cause wood rot or fungus and mildew to grow. That could compromise the integrity of the plywood as the added weight of the roof could lead to parts of the roof collapsing, leaking, or rotting.<\/p>\n\n\n\n