RESIDENTIAL PLAN
REVIEW
MAY 8th
DOHERTY INN
CLARE, MICHIGAN
MISCONCEPTION:
• Construction documents are not required for the
following: 1. One-and two-family dwellings
when the heating system input rating is 375,000
Btu’s or less. 2. When alterations and repair work
are determined by the mechanical official to be of
a minor nature. 3. Business, mercantile and
storage buildings having HVAC equipment only,
with one fire area and not more than 3,500 square
feet. 4. Work completed by a governmental
subdivision or state agency costing less than
$15,000.
LAWSUIT WAS AGAINST BCC
• A lawsuit was filed in Ingham County Circuit Court
against the Bureau and other State defendants over the
threshold requirement imposed for the submission of
plans. Discussions between the parties led to a settlement
of the lawsuit and modifications in the threshold
requirement. The new provision includes a base line in
Btu input rating of mechanical heating equipment, rather
than building size. This new criteria provides a better
representation of the complexity of the heating system,
based on equipment size rather than building area. This
new development provides for a threshold of more than
375,000 Btu input rating before plans would be required
for one-and two-family dwellings
If you copy BCC mechanical permit application
this automatically happens:
• The Bureau of Construction Codes has
established, based on the requirements of
section 106.3.1 of the Code and the State
Construction Code Act, a threshold for one- and
two- family dwellings at 3,500 square feet in
area. This threshold has been in place for
several years.
• Permit applications used by the Bureau will
reflect this modification as follows:
So what does the code say?
• M1401.3 Sizing. Heating and cooling equipment
shall be sized in accordance with ACCA Manual
S based on building loads calculated in
accordance with ACCA Manual J or other
approved heating and cooling calculation
methodologies.
DUCT DESIGN FOR
RESIDENTIAL
• M1601.1 Duct design.
Duct systems serving
heating, cooling and
ventilation equipment
shall be fabricated in
accordance with the
provisions of this section
and ACCA Manual D or
other approved methods.
DEVIL’S ADVOCATE
• So let’s say you abide by State parameter.
• So section M1403.1 & M1603.1 does not apply?
• So we can undersize duct & oversize or undersize
HVAC equipment?
• The only thing the statement says no plans are
required to obtain a permit.
• What happens when you get on a job you find
some serious design problems?
What do look for in a residential plan
review? Manual “J”
• Perform a room by room
heat gain and heat loss
calculated for each space
based upon its
orientation, exposed
surfaces and building
assembly U-values,
appliance loads,
occupancy, ventilation
requirements, duct loss,
and the activity and
function of the room.
On line calculator
• http://www.loadcalc.net/