Drywall installation has no differences in winter and summer time. The delivery of materials doesn’t make a big difference either. However most drywall contractors I talk to in Toronto know that taping, mudding and sanding take way longer in the winter than usually in the summer. The best and the fastest way for the mud to dry is low humidity and high temperature. In the winter every time when doors are open the heat is running away and the mud gets colder, it takes much longer to dry. On the other hand, if windows and doors are closed the humidity rises, the mud gets more moist and it takes longer to dry again. in order to achieve the best results and the shorter time for drying the drywall contractor should be knowledgeable enough and have enough experience to balance temperature and humidity. The house needs to be heated well ventilated by the means of fans and open windows. There should be nice timing for the windows to be opened so that humidity could reduce and closed after some time before it gets too cold which will lower the temperature of the sheetrock or compound and make drying time longer.
When professional drywall contractor gives you a quote they can never promise or guarantee the exact amount of time required of finishing the project, as it’s not possible because one never knows how long it will dry. From my experience I can predict with 95% accuracy how long it will take, but will never take a chance to guarantee, even though I can tell exactly how many days or even hours it will take to install drywall.
Remember, when choosing the professional contractor pay attention to their promises. If they guarantee the exact time for the project which is shorter, than that of all the other contractors, there is a big chance that the contractor is a novice in the business. The best way to find drywall and taping contractors in Toronto is either trough your friends or on www.homestars.com this site is very reliable with all the materials and reviews they provide. Of course no one is perfect so make your decision based on your research.