Windows, Doors & Safety

Size Windows, Doors, and Safety Systems Correctly

Window rough opening standards require adding 2 inches to the window width and 2.5 inches to the height — a 36x48 window needs a 38x50.5 rough opening. Get this wrong and the frame won't fit, costing you time and money on callbacks. These calculators handle the common sizing and safety questions that come up during window replacement, door installation, and home safety planning.

Windows and Doors

The Window Size Calculator determines rough opening dimensions for replacement and new construction windows by size and frame type. The Door Rough Opening Calculator handles interior, exterior, and sliding door openings — a standard 32x80 pre-hung door requires a 34x82.5 rough opening with proper shimming allowance. The Window Well Sizing Calculator determines the right egress window well dimensions based on window size and required clear area for code-compliant emergency egress.

Structural Safety: Snow and Drainage

The Roof Snow Load Calculator estimates the live load on your roof structure based on ground snow load (Pg) from ASCE 7 and roof geometry. A flat roof in a 50 psf ground snow zone carries a balanced snow load of approximately 35-40 psf — close to the structural limit for many older roofs. The Drainage Slope Calculator verifies that your gutter, drain tile, and surface grading slopes meet minimum requirements. Standard gutter slope is 1/4 inch per 10 feet; drain tile requires at least 1/8 inch per foot.

Radon, Fire, and Emergency Safety

The EPA Radon Zone Lookup shows your county's EPA radon potential zone — Zone 1 counties (predicted average indoor radon above 4 pCi/L) are high-priority for testing and mitigation. The Fire Extinguisher Guide recommends the right extinguisher type and size for kitchen, garage, and workshop locations. The Generator Sizing Calculator tallies the wattage of your essential circuits — a 30-amp transfer switch handles up to 7,500 watts, typically enough for refrigerator, well pump, furnace fan, and basic lighting.

Entertainment and Outdoor Systems

The TV Size Calculator and TV Viewing Distance Calculator help you choose the right screen size for any room. For a 10x12 ft living room, a 65-inch TV at 8 feet viewing distance is at the upper limit of comfortable viewing for 4K content. The Cord of Wood Calculator and Fire Pit Wood Calculator estimate wood needs for heating seasons and outdoor fires. The Outdoor Kitchen Gas Calculator sizes the propane or natural gas supply for grills, side burners, and outdoor heaters combined.