H-CHANNEL: Panels can be joined together using H-Channel or overlapped on 4' or 6' centers. H-channel is most effective when used where the sides of the panel have no structure behind them to screw to. If using H-Channel attach one panel to your frame while leaving about 1/8" gap in between that panel and the next one you are attaching. This leaves enough space for you to slide the H-channel into place. If you need a little more room for the H-channel, you can always trim the panel a little. Keep the screws approx. 1" from each side of the H-Channel. Do not screw into the H-channel. **Do not use H-channels on a roof, unless it is one continuous H-channel running from side-to-side. No H-channel clips on a roof. If H-channel is difficult to slide on, try spraying the grooves of the H-channel and the edges of the panels with a little WD-40, Pam or try rubbing a dry bar of soap on the edges or liquid soap on the edges of the panels and tap on the end of the H-channel with a rubber mallet.