Gingerbread Exchange Community

Yes, I have had this curving issue as well. I switched to the Gingerbread formula that appears on this site ("Construction Grade Gingerbread") a few years ago and I think that is when I first noticed this particular curving issue. I suspect that the curving has something to do with the lack of fat in the formula, not positive about that. However, please keep in mind that despite this curving tendency, I otherwise I find this formula to be BY FAR the best in terms of strength and durability.  And after all, strength and durability is what is most important in Gingerbread house dough. Therefore I would not suggest playing around with the formula or attempting to add fat to the recipe. This honey and egg dough formula, When properly made, results in a dough that handles extremely well and  When properly baked (and dried out correctly, as noted in the recipe) the end product will literally last for years (I have a large house made with this formula well over three years ago it's still in perfect condition.)

As far as the curling/curving issue, first of all, please make sure your cookie sheets are completely 'level' and not 'buckled' in places. It pays to invest in some good quality, heavy duty cookie sheets if you can.  I have some thinner sheets as well and have noticed that the curving is more likely on these than the really heavy-duty ones.  Also, I've noticed this curving tends to happen more on the so called 'cushion-air' type cookie sheets than those that are made of a single-sheet of heavy metal. Perhaps this is because the double/cushion-air-type don't allow the piece to bake through and dry out as well, I'm not positive about that though. 

The good news is that even if you do have the curving/curling problem, a little heat (a few seconds in the microwave, for example) will allow you to 'bend' the piece flat and I've noticed that once I decorate the pieces with royal icing or gum paste, they tend to stay flat; I suspect the icing keeps the pieces from curving again. Just please be sure that the pieces are completely cooled before you attempt to apply royal icing or cover with gum paste.  I hope this helps.

Thanks and happy Gingerbreading!
-Adam

as soon as i pop mine out of the oven i slide the piece onto the counter or table. i place a paper towel on top and then a book on top of that. after about 20 minutes i remove the book, place a new paper towel on the counter, peel my piece off the foil, lay it onto the paper towel, place another paper towel on top and place the book back on top. leave over night and perfectly flat pieces every time! the grease gets soaked up and no curling or warping at all for me.
maybe give this a go?