It would be unusual for a flat roof to suffer damage from the light snow Southern Arizona recently received.

QUESTION: Will our flat roofs in Southern Arizona stand up to the snow that will sometimes fall in the winter? Could the recent storm have damaged our roofing?

ANSWER: Homeowners all over Arizona were surprised by snowfalls last month and some have called us asking if a flat roof might be damaged.

You can take comfort in the fact that most flat roofs are built to stand weights of up to 20 pounds per square foot. So, you could probably get up to 4 feet of snow and have no problems. Those flat roofs should be fine.

You do want to watch out to be sure that water runs smoothly out of the scuppers on the roof once the snow starts melting. What happens is that plant debris can build up on the roof and then create a dam in front of the scupper when it snows. It’s a good idea to clean out scuppers from time to time.

Q: I want to have the windows replaced in my home but need to find out whether to use a retrofit window installation method in which the windows are installed into existing window frames? Is it better to remove the stucco, and then replace the window and its frame?

A: Due to the many types of windows that can be installed — perimeter pop outs, bay windows, and others — and due to the many different ways stucco can be finished — smooth, synthetic, lace texture, cats eye, and more — there is really not one answer that fits all solutions for window replacement.

A quality window replacement company can visit with you to determine the best solution for your conditions and make recommendations based on their experience and expertise.

Q: We recently moved into a new home and are concerned about plumbing issues. The shutoff valves for the toilets and sinks are all the push-pull plastic type. In other words, “push” to close the valve and “pull” to open. The supply hoses and the valves are PEX and are one unit with plastic couplings. But I know you recommend installing solid brass fittings and couplings. So, should we consider replacing these plastic units with solid brass, quarter-turn style valves with braided stainless steel lines and metal attachment nuts? The home has a two-year warranty against defects. But I do not want to run the risk of a major disaster. In addition, would replacing the PEX valves with new valves void the warranty?

A: The PEX pipe in your home is a really good product so you shouldn’t have any concerns about that. The valves on the other hand are a little less durable than the quarter-turn brass variety we prefer. Unfortunately, this isn’t a do-it-yourself job. You would need a licensed plumber to change them out as the connections between PEX and copper require special tools typically only available at plumbing wholesale outlets. Using these tools also requires having a plumber with experience to make the proper connections. As to the warranty question, ask your builder if the work involved would be considered an invalidation.

For more do-it-yourself tips, go to rosieonthehouse.com. Rosie Romero, an Arizona homebuilding and remodeling industry expert for 29 years, is the host of the Saturday morning “Rosie on the House” radio program, heard locally from 8-11 a.m. on KNST (790-AM) in Tucson and from 9-11 a.m. on KGVY (1080-AM) and (100.7-FM) in Green Valley.