Sunroom construction in Highland CA - a room built on a base that holds up

A four-season room is fully enclosed with all weather windows and is heated and cooled, while a three-season room or a screened porch has no heating or cooling. So the first thing I ask is whether you need the room comfortable every month or mostly want light and air through uninsulated windows or screens.

A sunroom in the San Bernardino area usually costs about $100 to $190 per square foot, which is a published local range and not our own price. Larger rooms that need a foundation and have heating and air conditioning fall at the higher end. Your own number comes from the estimate I write after looking at your house and base.

Sometimes, if the slab is in like-new shape. One sunroom maker's installation guide prefers a new slab or deck and says an existing one needs to be in "like new" condition, because numerous buckles or cracks make a slab unsuitable and could lead to leaks. I check yours at the estimate, and if it's worn, replacing it first is usually the better call.

Ask Highland Building & Safety, which issues permits for additions in the city. Its permit list names work like family rooms, decks, reroofing and heating and air conditioning but doesn't name sunrooms, so call 909-864-6861, ext. 232, with questions about your design, and know that the city says some designs go past its standard handouts and need engineering from a design professional, which comes up most with custom rooms. If your lot is in a fire hazard severity zone, the same wildfire building rules generally apply in any zone, and the city has posted the State Fire Marshal's map published in March 2025, so you can see where your property sits before we start the design.

A contractor licensed by the Contractors State License Board, whenever the project needs a building permit, uses additional workers or costs $1,000 or more in labor and materials. The board licenses anyone who builds or alters structures in the state. We're licensed and fully insured, and I'm happy to go over that at the estimate.

Settle the insulated windows and the insulation in the walls, floor and roof in the first plan, because they're much easier to put in while the room is being built and adding them later can often cost more. One sunroom builder's guide also says a well-insulated solid roof saves more energy in winter and lets in less of the sun's heat in summer than a glass roof, and that conventionally framed rooms generally cost less than high-performance glass roof rooms. The state Energy Code sets efficiency requirements for additions to existing homes too, so those are part of the design from the start.