What is the standard weight capacity of a residential stair lift? Holds up to 250 lbs. 100% Get Free Quotes Today! Question: What is the standard weight capacity of a residential stair lift? Top Answer (100% of 2 votes): Holds up to 250 lbs. . Answer: Holds up to 250 lbs. Explanation: We usually recommend the Pinnacle from Harmar which has a 300LB capacity Guardian Home Modification & Safety Solutions Get Free Quotes Today! Find Local Pros Free Stair Lift Installation Cost Estimates Related Questions How Much Would It Cost to Install a Stairlift? How is a stair lift attached to the staircase?Top answer: The stair lift is attached directly to the stairs. Is it possible to install a stair lift outdoors?Top answer: In most cases Is it possible to install a stair lift on a spiral staircase?Top answer: In most cases How long does it typically take to install a stair lift? (straight stairs; two-man crew)Top answer: 2-4 hours