Building on a hillside in Fairfax: the local rules

Each rule below links to the section of the Fairfax Municipal Code it was read from, with the code text one click away (checked October 2026). General information, not legal advice.

What Fairfax's code says

Fairfax code What Fairfax's code adds
Grading and retaining walls	Keep cuts, fills and retaining walls to a minimum, except those needed only for foundations. Applies: Projects under the Planning Commission's ridgeline and hillside review criteria, unless the commission grants an exception. § 17.060.050 · code text Cuts, fills and retaining structures will be minimized except as reguired exclusively for foundations.
Height on hillside lots	No part of a building may be taller than 28.5 feet. Applies: Upslope lots under the ridgeline and hillside review criteria; measured from natural or finished grade, whichever is lower. § 17.060.050 · code text No part of a building's height shall exceed 28.5 feet on an upslope lot and 35 feet on a downslope lot, 24 feet within 20 feet of a front property line on an upslope lot, and 24 feet at a rear setback line, measured to the adjacent natural or finished grade, whichever is lower. No part of a building may be taller than 35 feet. Applies: Downslope lots under the ridgeline and hillside review criteria; measured from natural or finished grade, whichever is lower. § 17.060.050 · code text No part of a building's height shall exceed 28.5 feet on an upslope lot and 35 feet on a downslope lot, 24 feet within 20 feet of a front property line on an upslope lot, and 24 feet at a rear setback line, measured to the adjacent natural or finished grade, whichever is lower. No part of a building may be taller than 24 feet. Applies: Within 20 feet of the front property line on upslope lots; 1 extra foot if the part above 24 feet steps back 1 foot. § 17.060.050 · code text No part of a building's height shall exceed 28.5 feet on an upslope lot and 35 feet on a downslope lot, 24 feet within 20 feet of a front property line on an upslope lot, and 24 feet at a rear setback line, measured to the adjacent natural or finished grade, whichever is lower. No part of a building may be taller than 24 feet. Applies: At the rear setback line, under hillside review criteria; 1 extra foot if the part above 24 feet steps back 1 foot. § 17.060.050 · code text No part of a building's height shall exceed 28.5 feet on an upslope lot and 35 feet on a downslope lot, 24 feet within 20 feet of a front property line on an upslope lot, and 24 feet at a rear setback line, measured to the adjacent natural or finished grade, whichever is lower.

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What extra rules apply to a hillside lot in Fairfax?

Fairfax's code: Keep cuts, fills and retaining walls to a minimum, except those needed only for foundations. (Projects under the Planning Commission's ridgeline and hillside review criteria, unless the commission grants an exception.) (§ 17.060.050); No part of a building may be taller than 28.5 feet. (Upslope lots under the ridgeline and hillside review criteria; measured from natural or finished grade, whichever is lower.) (§ 17.060.050).

Building on a hillside in Fairfax

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