Concept Commercial Roofing

Concept cold called on us to give an estimate on repairing / replacing our roof. While he was here, they asked if we had any immediate issues. I showed him an area where a leak had occurred. He told me that he would repair the leak for $450.00. When I told him I would like to have some time to consider it, he told me that he had his men in the area and would do the work for $300.00 with a one year guarantee. I agreed and they showed up to do the repairs. Once on the roof, they found that their propane tank that they use to torch down the patches was empty. He said that he would be back in an hour with a replacement. It was 4:45 on a Friday and we were closing for the day. He told me that "it would only take a half hour to make the repair". I called him on the amount he quoted for 2 men to do a half hour worth of work with minimal materials needed. I just shrugged it off because I did agree to the price. He then received a phone call and he told me he would be back Monday after all. He did come as promised. I paid him and off he went. The very next rain storm my roof leaked as before. I called him, he answered and told me he would be here tomorrow. After 7 messages left, and emails. He is nowhere to be found. Buyer BEWARE!