Joe Hagerman, DOE Representative

Analysis by Pacific Northwest National 

Laboratory 8/18/2014

Manufactured Housing Working Group 

Preliminary Energy Analysis in Support of the Manufactured Housing Rule

August 21-22, 2014
2

Description of the Analysis

• Two prototype manufactured housing 

models: 

– Singlewide (14’x66’)

– Doublewide (28’x56’)

• Four commonly used heating fuels/systems: 

– Electric resistance (SE=1) 

– Electric heat pump (HSPF=7.7)

– Natural gas furnace (AFUE = 0.78)

– LPG furnace (AFUE = 0.78)

– Cooling Equipment (SEER = 13.0)

Singlewide (14’x66’)

Doublewide (28’x56’)
3

Description of the Analysis (cont’d)

• 15 locations representing 15 

climate-zones defined by the 

International Energy Conservation 

Code (IECC). Same 15 locations 

mapped to the three HUD zones for 

HUD code analysis

• Five Code scenarios: HUD Code, and 

the 2006, 2009, 2012 and 2015 

editions of the IECC

• A full set of 600 EnergyPlus building 

energy models were used.

– Used Building America schedules and 

loading 

– Modeled results at 1-hr increments for 

an entire year!
4

• The purpose of this PNNL analysis is to estimate the energy use 

and operating expenses. 

• For this purpose, PNNKL identified building parameters at the 

component level, such as...

– Insulation for walls, ceilings, floors

– Window U-factor and SHGC

– Envelope leakage (infiltration) and duct leakage

– Lighting

– Hot water pipe insulation etc. 

Analysis Assumptions
5

• The current HUD Code only prescribes overall U-factors (Uo).

– The overall U-factors (Uo) prescribed by HUD Code have to be 

translated to building component insulation values for energy use 

analysis purposes

– A spreadsheet (“PNNL MH Uo Calculation Spreadsheet “) has been provided 

to go between building components and overall U-factors (Uo) for HUD 

Code

• For all IECC codes analyzed, IECC provides requirements at the 

building component level

Analysis Assumptions (Cont’d)
6

Analysis Outcomes

• PNNL provided two spreadsheets to the WG:

– PNNL MH Analysis and Results Spreadsheet that contains 

all the results from the analysis along with a detailed 

documentation of assumptions used in the analysis

– PNNL MH Uo Calculation Spreadsheet that documents the 

conversion of building component R-values to a wholebuilding overall U-factor (Uo) for each code scenario 

considered in the analysis 

• PNNL is prepared to support more analysis and 

simulation runs requested by the WG.
7

Interpreting Results

• The results are structured in the PNNL Analysis spreadsheet:

– The first tab, Input, documents all assumptions used in the analysis

– Results are presented on the other four tabs of the analysis 

spreadsheet

– The tabs Singlewide_EUI, and Doublewide_EUI show Annual Energy 

Use Intensities (EUI) in kBtu/ft2-yr for the Singlewide and the 

Doublewide house configurations respectively

– EUIs are reported separately for heating, cooling, domestic hot water 

and lighting end-uses for each code scenario analyzed and for each 

climate-zone

• Similarly, tabs Singlewide_Cost, and Doublewide_Cost show 

corresponding annual energy costs ($/yr) by end-use for each 

climate-zone and for each code scenario analyzed
8

Interpreting Results (cont’d)

• EUIs and annual energy costs (operating costs to consumers) 

are presented for each of the four heating systems separately 

in tables A through D on each EUI and Cost tabs

– Fuel prices for electricity, natural gas and LPG are national average 

prices derived from EIA

• Aggregated results calculated using heating system shares are 

shown in table E on each EUI and Cost tabs

• The Working Group members should interpret the results on 

their own

– But do not hesitate to ask DOE for more explanation, assumptions or 

other information about the results.
9

• QUESTIONS?
Matthew Walker

Navigant Consulting, Inc.

Supporting the WG

Manufactured Housing Working Group 

Life-Cycle Cost Analysis Overview

August 21-22, 2014
11

Life-Cycle Cost (LCC) Analysis Overview

• LCC represents the full cost of ownership for one consumer

• Current analysis focuses on incremental first cost and 

incremental operating expenses

LCC Results

Operating Expenses

Convert to 

Present 

Value

HUD Code

LCC ($)

Efficiency (Decreasing Uo)

LCC STATUS:

Structure and calculations of the model are in 

place. Inputs on cost data and other 

assumptions are needed!

First Cost

(Housing Purchase)
12

Financial Parameters

Parameter Description

Discount Rate Time value of money; Alternative investment rate

Analysis Period Duration of analyzed operating expenses

Mortgage Interest Includes real estate and personal property (chattel)

Loan Term Period over which the loan is repaid

Down Payment Percentage of purchase price paid upfront

Loan Fees and Points Fees paid upfront in addition to down payment

Property and Sales 

Tax Rate

Taxes paid based on value and price of home

Fuel Prices and 

Escalation Rate

Price of electricity, gas, etc. and expected annual increases

Financial parameters impact the calculation of the tradeoffs 

among first costs and different operating expenses.

The WG needs to agree on the Financial Parameters to aid the LCC.
13

First Costs

First costs are associated with the housing purchase.

• The housing purchase includes down payment, mortgage, taxes, fees

• All Energy Efficiency Measures (EEM) analyzed are assigned costs

– LCC requires end-user (retail) prices (Manufacturer costs can be adjusted 

with a markup)

• EEM requirements may allow for smaller (less expensive) heating and 

cooling equipment

• EEM requirements may change 

 installation cost (e.g., delivery)

Example

Insulation Cost

R-11 Cost

R-19 Cost

R-21 Cost

The WG needs to collect EEM, installation, and modified heating/cooling 

costs to aid in determining the First Costs.
14

Operating Expenses

Operating expenses are calculated on an annual basis and 

discounted to their value in the present year.

• Annual energy cost

– Calculated with EnergyPlus results and EIA fuel cost data

• Maintenance related to usage of different EEMs

The WG needs to collect maintenance costs (if applicable) to aid in 

determining the Operating Expenses.
15

Other Assumptions

Both the individual and aggregate impact on different 

consumer categories can be analyzed.

• Percentage of heating/cooling equipment types within a 

climate zone

– Natural Gas, propane (LPG), heat pump, electric resistance

• Percentage of consumers using real estate vs. personal 

property loans

• Percentage of consumers buying single- vs. double-section 

homes

The WG needs to collect and agree upon other important data for the LCC.
16

• QUESTIONS?