How do you calculate spacing for board and batten?

To calculate board and batten spacing, subtract the total width of all your vertical battens from the total width of your wall. Then, divide that remaining space by the number of gaps (which is always one less than the number of battens) to find your exact spacing distance.

What is the standard gap between board and batten?

While it depends heavily on the size of your wall and personal preference, a standard spacing gap for interior board and batten is typically between 12 and 20 inches. Smaller gaps create a more traditional wainscoting look, while wider gaps (16+ inches) give a more modern, craftsman feel.

Should I start my battens in the middle or the edges?

Always start by securing your two outer edge pieces flush against the adjoining walls or corners. Once the borders are set, use a spacer block cut to the exact gap measurement provided by the calculator to easily nail your interior battens in place.

Range Hood CFM Calculator | Free Vent Sizing Tool

Range Hood CFM Calculator

Cooktop Type

Cooktop Width (in inches)

Minimum Required CFM

Introduction

Planning a kitchen remodel or upgrading your ventilation? Stop guessing how powerful your exhaust fan needs to be. Use our free Range Hood CFM Calculator below to find the exact minimum airflow required to keep your kitchen clear of smoke, grease, and odors based on your specific cooktop.

How do you calculate CFM for a range hood?

To calculate the required CFM for an electric or induction range, multiply the total width of the cooktop in inches by 10. For a gas range, you must calculate by heat output instead of size; divide the combined total BTUs of all burners by 100 to find your minimum required CFM.

How to Take Your Measurements

Getting the right ventilation requires inputting the correct specifications from your kitchen appliances.

For Electric & Induction Ranges: Measure the total width of the cooktop surface from left to right. Standard residential sizes are usually 30 or 36 inches.
For Gas Ranges: Do not use the width. Instead, consult your manufacturer’s manual to find the BTU (British Thermal Unit) rating for each individual burner. Add them all together to find your total heat output.

The Formulas Used

This calculator is built using the standard ventilation guidelines recommended by the Home Ventilating Institute (HVI).

Electric & Induction Formula For electric ranges, the math is based strictly on the physical size of the cooking surface to ensure enough canopy capture area: $$ \text{CFM} = \text{Cooktop Width (inches)} \times 10 $$

Gas Cooktop Formula Gas burners generate significantly more ambient heat and combustion byproducts, meaning the ventilation requirement is based on raw power rather than physical size: $$ \text{CFM} = \frac{\text{Total BTUs}}{100} $$

Frequently Asked Questions

Q. Do I need to account for kitchen size?

A. Yes. While this calculator provides the baseline CFM required for the stove itself, standard building practices also recommend that your range hood should be able to exchange the entire volume of air in your kitchen 15 times per hour.

Q. What happens if I buy a range hood with too much CFM?

A. If you install a powerful commercial-grade hood (typically anything over 400 CFM) in a highly insulated modern home, you may be required by local building codes to install a “Make-Up Air” system. This prevents the powerful exhaust fan from creating negative pressure inside your house and pulling dangerous carbon monoxide out of your furnace or water heater flues.