3 Story vs. 4 Story vs. 5 Story Apartments

by EVstudio AEP on August 2, 2018

We recently did a search for a good synopsis of the basic differences in costs and requirements for different heights/stories of apartment buildings. Finding none we decided it was time to fix that.

3 stories

Type VB construction does not require rating of the structural frame.
(Just ratings between units and corridors)

No elevator required
Ground floor accessible

4 stories

Type VA construction you need to rate ANY beam that fall under certain restrictions
Type I podium with Type VB above 3 hr Floor
Elevator Required by ADA
All Floors Accessible (This means more Type B units, not that they are really changed from floor to floor)
NFPA 13R Fire Sprinkler System

5 stories

Type III construction, 2 hr rated exterior walls (with fire retardant treated wood), and rated floors for Type IIIA
Type I Podium with Type VA above 3 hr floor
Elevator Required by IBC and ADA
All Floors Accessible
NFPA 13 Fire Sprinkler System (Sprinklers in cavities)
Increased detailing for differential shrinkage of wood (Brick relief joints etc)
Increased shear wall detailing and increased structure on bottom floor

Image Courtesy of the American Wood Council

Image Courtesy of the American Wood Council

Originally posted 2014-11-13 07:55:57. Republished by Blog Post Promoter


{ 2 comments… read them below or add one }

Dean Dalvit October 18, 2018 at 7:28 am

That is because at five stories, you have to go from type V construction to type III construction. Can still be wood frame, but it needs to be fully fire rated and therefore is very uneconomical to do. As a result, you don’t see a lot of five story wood framed buildings.

Juliane Workley September 25, 2018 at 11:30 am

Great information. However, there is no cost per sf for the 5 story wood construction; only for the 3 and 4 story types.

Leave a Comment