Using H Clips Under Metal Roofing

We are often asked if clips are engineered and the answer is.

Using h clips under metal roofing.

This type of underlayment is critical to a quality roof installation. For many applications a layer of plywood underneath your metal roofing is an unnecessary expense. Metal roofing panels rated for architectural use attached to purlins horizontal pieces of wood or metal fastened to roofing trusses are structurally sound when installed according to your roofing manufacturer s instructions and local building codes. You may need to cut panels to fit angles using a circular saw with a metal saw blade.

H clips provide additional stiffness between bearing points for the unsupported edges of wood panel plywood or osb roof sheathing along with the necessary 1 8 gap for expansion as shown below illustrated on a bag of simpson h clips. It serves as a moisture barrier as well as a slip sheet. When hot roof construction is done a roof with no ventilation a breathable underlayment is recommended. The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process.

What is referred to as an engineered clip is a clip specified for use in an engineered metal roofing system which is tested to follow the strict guidelines and industry standards just because a clip is used in engineering it still has to be installed per the manufacturer s recommendations. Not always required but a good idea. Lay the starter row of metal shingles at the drip edge and affix to the roof with metal roofing nails. It will help you to eliminate problems that may come when the house becomes extremely cold in the winter and terribly hot in the summer.

Some older h clips do not provide a built in gap. Polyurethane spray foam metal roof insulation. In order to add moisture barrier under metal roof you can spray the undersides of the roof by using a thick layer of polyurethane spray foam. Metal roofing is also available in the form of shingles.

If an open grid framed roof or widely spaced old solid roofing planks as the sheathing it is important to tightly stretch this so it does not sag down and hold water between the framing roof sheathing boards and the metal roofing obviously far better to put down a solid sheet sheathing first when doing a reroof in that sort of situation. Once again this is used on cold roof construction.