AboutRoger Zona Expertise I am experienced in all types of construction: residential, industrial and commercial; single family, multi-family, mid-rise and high rise buildings (16 story) as well as remodeling, additions and tenant improvements. I can field most any question that relates to general construction. I have consulted with infrastructure (utility) contractors also and have a good general knowledge of underground utility construction for subdivisions and commercial projects.
Experience After college, I began my career in automotive engineering. After 4 years I chose to become an apprentice Architect; 4 yrs later I opened my own architectural firm. Six years later I moved to Florida to buy & develop land and build. I became a State Certified General Contractor and operated my business for 40 years. I built all types of residential and commercial buildings including warehouses, shopping centers, high rise apartment and office buildings and developed sites for other contractors. I retired and became a consultant to the construction industry. I maintain my license and continuing education requirements, operate a small construction company and write a weekly newspaper column for the Palm Beach Post (a Cox publication) with the byline "Ask The Contractor". I am the "technical editor" for a publisher of books that relate to home maintenance.
Question QUESTION: Last year I hired a local concrete guy to come and do the steps up to my house and the sidewalk in front. He did this in two sections, half the sidewalk in one and the other half and the steps int he other. He wa svery late getting to it and the first half was poured in early november. The last part he didn't get to until mid december. He assured me that he had extra cement added to it, and he covered it with blankets to keep it warm. It got very cold here shortly after, and the blankets were removed after the snow and ice was gone (two weeks). The surface appears blotchy now, like it's a different color where the blanket was touching it and lighter where a wrinkle might have been. It looks very different from the other part of the sidewalk. I have asked a different contractor in the area if it could have frozen, and he said it would have already been spalling if it had done that. What is causing my discoloration though? Is there anything I can do about it?
ANSWER: Dear Michael,
Concrete in the winter can be a problem. Adding extra cement is not necessarily recommended. More concrete is added for additional test strength. He should have added an add-mixture of anti-freeze. This is common for pours that may experience freezing. It slows down the evaporation of water and prevents the water from freezing and spawling.
As for the discoloration - there are several good concrete "Stains" on the market. Not a paint, which stays on the surface but a penetrating stain. It comes in many colors including gray if you want the concrete to look like concrete. Another method may be to acid wash the walk or use a concrete cleaner. This method may not give you the best results and is more commonly used when concrete gets stained by oil or paint. Contact your local concrete plant and they can give you some help about stains, cleaners, etc.
I hope this has been helpful.
Roger
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QUESTION: Are there any long term effects of this?
Answer Michael,
I don't quite understand what you mean by "long term effects". Concrete will change with age and weathering but that will take some time. Concrete is a natural product and "what you see is what you get". To get a more uniform color, the best solution is concrete stain. You can even create a pattern on the walk. Using a clear wax marker, draw a stone pattern and use two or three stains in the same color family. The wax leaves a "grout" effect.
Good luck.
