Proposal to further amend city’s ADU ordinance fails to gain support

A proposal to amend the City of Waltham’s ordinance on accessory dwelling units and allow for more, and potentially larger, ADUs by right failed to get past the City Council’s Ordinances and Rules Committee.

On Monday night, Councilor-at-Large Colleen Bradley-MacArthur proposed that the committee add language to the amendment saying that ADUs could be up to 75% of their principal dwellings’ total surface area.

Following Bradley-MacArthur’s request, Ward 8 Councilor Cathyann Harris asked the committee if any members would like to make a motion to amend the ADU ordinance as proposed, but no such motion was made. The committee then sent the ordinance back to the City Council table for a second reading.

ADUs became permitted by right in Massachusetts earlier this year as part of the Affordable Homes Act. ADUs are small, independent living spaces located on the same lot as a principal dwelling in a single-family residential zoning district. They are often stand-alone structures or converted basements and attics. 

The Affordable Homes Act states that ADUs cannot exceed 900 square feet or 50% of the principal dwelling unit. 

Bradley-MacArthur, speaking in favor of her proposed amendment, said by increasing the percentage threshold for ADUs, the city could boost the number of ADUs added to the city’s housing stock. 

“We’re not quite close enough to the true spirit of the law, which is to adopt more permissible zoning,” she said.

Bradley-MacArthur told the committee that this additional amendment would make the ordinance more inclusive, explaining that residents who could not build under the state law could build ADUs in Waltham if the city raises the percentage threshold.

Although Bradley-MacArthur’s proposed amendment failed to move forward, another proposed amendment to the ADU ordinance is moving ahead. 

That proposal seeks to amend the city’s ADU rules to increase the minimum size of ADU units from 300 to 450 square feet. That ordinance has been making its way through the legislative chambers.

The Ordinance and Rules Committee on March 19 voted 2-1 to approve that amendment to the city’s ADU ordinance. Council President John J. McLaughlin and Ward 3 Councilor Bill Hanley voted for that amendment. Ward 9 Councilor Robert G. Logan voted against the amendment. Harris did not vote, and Ward 2 Councilor Caren Dunn was not present.

Hanley introduced the amendment to change the minimum unit size from 300 square feet to 450 square feet, saying the increase would make the units feel less like dorms and more like homes.

Logan said that increased size will impact the number of ADUs that could be built in the city, saying it would reduce the number of houses in Waltham eligible to build an ADU on their lots by right by 160.