Question
My understanding is that installing a glass storm door over a wood entry door may be a bad idea. Therefore I have never done it. I have seen problems that were blamed on such installations in the past. More specifically cracked panels in a manufactured white oak door a builder installed. Failure occurred after only a year or two. There certainly could have been other causes, but this is what I was told. I never really discussed this with anybody who actually builds doors. Given a hypothetical situation - glass storm door, northern New England (brutally cold/dry winter, moderately hot/humid summer whether) and strong afternoon sun exposure. Would you agree or disagree that glass storm doors over a wood entry door are a bad idea?
Forum Responses
(Architectural Woodworking Forum)
From Contributor H:
I think the key to this is the fact that the door will have significant exposure to the sun. I've seen that cause problems on a wood door here in southern New England. However that door was painted black which aggravated the situation. Plus the owner left the glass storm door in place year round. Summer heat buildup between the door and storm panel was pretty significant. Other than that one situation I've not seen problems on well-built doors. I've seen plenty of splitting on thin panel doors but that has been on both interior and exterior use. I'd say that as long as you maintain a good thick door panel that floats freely within the frame you should be fine. I would stay away from pine which has significant seasonal movement and if possible would go with quarter sawn material for stability. Additionally I'd advise the customer to use lighter color paints if possible and to swap over to a screen in the summer to prevent heat buildup on the exterior surface of the door. While a well-built door should stand up to this heat buildup the finish will be sorely tested.
Even the storm door people admit that their doors can become solar collectors, and recommend in such situations, a 3/4" gap at both top and bottom of their doors. Try to explain that to someone wanting to save energy. We have always discouraged storm doors, since the primary door is well built and insulated and weatherstripped, there is no need for more protection. In some cases, we have fitted combination doors so they can have a storm panel in winter months, replaced by a screen panel for the rest of the year. Or even a storm (only) door on lift-off hinges, so it can be used only in the winter, and easily removed and stored the rest of the year. When one of our doors developed hairline cracks, we were told the door was falling apart. The flat black door was south facing, no overhang, and hot as heck. The surface measure 195 degrees. Small cracks had opened in the panels and at most of the cope/stick joints. We recommended a repaint, with at least a gloss black, if not another color entirely, and explained how this door violated the warranty at several key points.
An old guy story: When I first started in a real professional shop many years ago, I occasionally was given a job of replacing plastic decorative door moldings that snapped onto metal doors. These plastic moldings appeared melted by heat, sagging and distorted. I assumed a house fire and the door was salvaged. I dutifully made new in wood and assembled them with reinforced miters so they could go back up, last and look good. I did several of these before I found out it was heat from the un-intentioned solar collector that was created by the tight fit of a storm door, dark paint and southern exposure.
