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What are Density Bonuses? What is IIHO?

Why are current IIHO ordinances skimpy on details and long on promises?

IIHO stands for Integrated Innovative Housing Ordinance. The main Part of IIHO is intended to support innovative housing per RSA 674:21. IIHO Regulations dictate everything and anything related to town development: various types of housing, recommendations for open space and conservation, types of developments, impact fees, growth management, etc. Most importantly, IIHO regulations override existing zoning. That’s right, through IIHO our Planning Board members can throw out zoning laws completely. See next question.

What are Amherst’s local zoning ordinances that can be waived? Basically, all of them, the IIHO is in itself a zoning ordinance.

Amherst is divided into several different “zones” all with their own basic permitted uses. You can see the map here:

Zones range from commercial to industrial to residential. Each has basic rules as to what structures can be built, can it include a business, can it be housing? The basic zone for housing is a residential zone, and the basic allowable build for this zone is one house per 2 acres.

What is a density bonus?

Based on the IIHO (Section 4.16 of the Amherst Zoning Ordinance) depending on what type of building a developer is proposing or how much “accessible” open space there will be in the planned development, a percentage bonus is awarded that increases how many “structures” can be built on that 2-acre lot.

For example, on a 20-acre lot, based on basic zoning, you could technically build 10 houses. Let’s say the developer is building 65+ housing (30% bonus), single floor units (10% bonus) with two bedrooms (10% bonus). There will also be handicap accessible units (15% bonus) and sidewalks (10% bonus). There is also going to be a community center that will be open for the public to rent (25% bonus). Doing the math, that’s a 100% bonus; 100% of 10 houses is 10 more houses, so overall, the 20-acre development can now support 20 houses.

The developer makes more money to more dense they make the land. Think about that!

Right now, the IIHO has NO CAP on the density bonus to be granted. At the 1-15-20 Planning Board Meeting, a presentation was given showing that most of the IIHO developments were well in excess of 100% bonuses, even up to 165%.

Simply looking up density bonuses on the internet, ( states “Typically programs allow increases of between 10 percent and 20 percent over baseline permitted density…”. Even LA City Ordinance only grants a 35% bonus ( ).

4.16 IIHO also does NOT LIMIT location of these developments, even when land use sites such as recommend Areas Most Suited to High-Density Development are:

· Areas with existing infrastructure

· Areas where existing public infrastructure can be easily extended

· Areas where development will not adversely impact significant natural systems

· Areas where existing community character will not be adversely impacted

IIHO is not the only way to encourage Innovative Housing for a growing town! There are other ways using existing zoning to create sustainable and appropriate growth, including affordable housing to support the blossoming economy in NH. IIHO looked great on paper but in reality, it ends up missing the mark and putting the town at risk in the end. 4.16 IIHO must be removed and replaced with a growth plan that provides consideration for the Historic nature of this town, incorporates input from land use groups, lessons from larger cities and other NH towns, and especially input from Amherst residents.

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