building science final project

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FINAL PROJECTEnergy requirements and comfort Analysis for House Apt. and Building

BLDG 6611 / 2 Building Science

Presented To

Dr. Hashem Akbari

Prepared By

Ricardo Jose Morales Silva ID: 7164084

November 27, 2014

TABLE OF CONTENTS

I. Table of ContentsI. ABSTRACT.............................................................................................................................. 3

II. Introduction...........................................................................................................................4

III. Methodology......................................................................................................................... 7

A. Weather design parameters...............................................................................................7

B. Building Data.....................................................................................................................11

IV. CALCULATIONS.................................................................................................................... 11

A. U factor walls....................................................................................................................11

B. U factor Roof-Ceiling.........................................................................................................12

C. U factor windows..............................................................................................................13

1. Windows Schedule....................................................................................................13

D. Infiltration..................................................................................................................... 14

E. VENTILATION.................................................................................................................... 16

F. COOLING LOAD.................................................................................................................16

1. Opaque Surfaces........................................................................................................16

2. Transparent Fenestration Surfaces............................................................................18

3. Infiltration Load.........................................................................................................22

4. Internal Gains............................................................................................................23

5. TOTAL COOLING LOADS.............................................................................................24

G. HEATING LOAD..............................................................................................................25

1. Exterior Surfaces Above Grade (walls, doors, ceilings or windows)...........................25

2. Ventilation and Infiltration........................................................................................26

3. TOTAL HEATING LOADS.............................................................................................27

V. REFERENCES.........................................................................................................................31

TABLE OF FIGURES

Table 1 -Table 1 ASHRAE Fundamentals 2009 Ch17.3...................................................................6

Concordia University Page | 1

I.ABSTRACT

The purpose of this report is to analyze in detail the energy requirements for comfort in a student residence unit and entire house building. The study will be conducted for Cooling and Heating comfort conditions. And recommendations to improve energy-comfort efficiency will be given.


II. Introduction

This report will analyze a Quadruplex Residential building divided into four apartments and located in 196 Ch Cote St-Antoine, Westmount, QC.

The building was constructed is the 1930’s using clay brick and wood materials. During the following decades it has being renovated and equipped with modern fixtures and appliances. Heating is provided by convection electric heater and cooling is made by mini-split air conditioner units.

Appliances installed consist of one electric stove, one oven, one fridge, one washing machine and one dryer.

Detail calculation will be performed for the unit on second floor using the Residential Load Factor Method based on ASHRAE Fundamentals 2009 parameters to estimate the energy requirements for comfort (Cooling & Heating). For obtaining the complete building energy requirements, simulation will be conducted using eQuest energy simulation software.


Figure 1 : Building Front view

Fig.1 show the front view of the building where the typical 1930’s clay brick construction can be appreciated.

The location of the property is easily accessed by bus routes 24, 138 and 104 that connects with Green and Orange metro lines. Concordia University is located at 12min either by bus (route#24) or by bicycle. Conveniently located relatively close to mayor shopping centers, grocery stores, local services, and parks without the complications of downtown conglomerate. Fig.2 shows the map location of the building in the study.

In Fig.3 the apartment distribution can be appreciated. Consisting of 2 Rooms, 1 Master, 2 Bathrooms, Laundry room, Living room, Kitchen and Dining Room.


Figure 2 : Building Location -Source Googles map


Figure 3 -Top Floor Plan Apt.2

III. Methodology

Calculations are performed following the Residential Load Factor Method (RLF). ASHREA 2009 Fundamentals describe the Residential Load Factor Method as a simplified method obtained from thousands of ResHB Method heat and cooling results, where different climates and construction types where used. After comparing with RLF method the values obtained are in the order of a 10% error considered an acceptable range for the study.

Heating and Cooling factor with RLF calculations will be obtained separately following the method steps described.

In order to validate the calculation of RLF method, the building to be analyzed must follow the criteria described in table-1.

For the present project, in the case of the House to be analyzed the requirements are fulfilled, where the parameters given for Montreal are: Latitude 45.55oN, Elev: 55m (above sea level), All fenestration surfaces are vertical and building use is for residential occupancy.


Table 1 -Table 1 ASHRAE Fundamentals 2009 Ch17.3

A. Weather design parametersAccording to ASHRAE Fundamentals 2009 Ch14 the design conditions are given in table 1 showing Annual Heating, Humidification Design Conditions, Coldest / Hottest month, Latitude, Longitude, Elevation, Standard pressure at elevation and Time zone. All this parameters are required in order to perform the RLF Method calculations.

From tables the information given for the closet location selected correspond to:

MONTREAL/PIERRE ELLIOTT TRUDE

Location: MONTREAL/PIERRE ELLIOTT TRUDELatitude: 45.47o NLongitude: 73.75o WElevation: 36 m above sea level

Winter parameters: Heating Calculations (Jan-21)( Values ASHRAE Fundamentals 2009 Ch143 & Psychrometric Chart )

Dry Bulb Temperature: (DB) -21.1 oCWet Bulb Temperature: (WB) ----------Relative Humidity: (RH) ----------Dew Point: (DP) -27.9 oCEnthalpy (h) -20.432 kJ/Kgda

Humidity ratio (W) 0.2913 gw/Kgda

Pressure 762.3 millimeters of mercury

Summer parameters: Cooling Calculations (July-21)( Values ASHRAE Fundamentals 2009 Ch143 & Psychrometric Chart )

Dry Bulb Temperature: (DB) 28.5 oCWet Bulb Temperature: (WB) 21.1 oCRelative Humidity: (RH) 52%Dew Point: (DP) 16.8 oCEnthalpy (h) 61.5 kJ/Kgda


Pressure 761.3 millimeters of mercury


Figure 4 -ASHRAE Fundamentals 2009 Ch14


Summer

Winter

Indoor parameters:Summer ( Typical Values assumed ASHRAE Fundamentals 2009 Ch17.3 & Psychrometric Chart)

Dry Bulb Temperature: (DB) 24oCWet Bulb Temperature: (WB) 17 oCRelative Humidity: (RH) 50%Dew Point: (DP) 13 oCEnthalpy (h) 47.5 kJ/Kgda


Indoor parameters:Winter ( Typical Values assumed ASHRAE Fundamentals 2009 Ch17.3 & Psychrometric Chart)

Dry Bulb Temperature: (DB) 20oCWet Bulb Temperature: (WB) 11 oCRelative Humidity: (RH) 30%Dew Point: (DP) 2 oCEnthalpy (h) 31.5 kJ/Kgda



Apartment Indoor Conditions

Summer

Winter

B. Building Data

Description AreaTotal Apartment Surface area 134m2

Total Apartment Perimeter 52 mTotal Apartment Perimeter wall area (h=3m) 156m2

Total Window Area (10 u.) 17.9 m2

IV. CALCULATIONSA. U factor walls


3 wythes clay brick

Total 12 in15 Lb. black building

paper Air space 1in

Wood Furring (Plywood) ½ in

Plaster-Paint finish

INOut

Determine the Conductance and Resistance of the wall assembly:

Element Thickness ( l )Conductivity

k ( Wm K )

Conductance

C ( W

m2 K )Resistance R

(m2 KW )

clay brick 12 in (0.30048m)

1.21 4.0 0.248

15 Lb. black building paper

--------- 8.3 0.78

Air Spaceε = 0.90(still air)

1 in (0.0254m) 0.211 8.3 0.12

Plywood Sheathing ½ in (0.013m) 0.115 8.85 0.113

Plaster finish 0.003m (3mm) 0.23 76.7 0.013

Total U Total Resistance

0.78W

m2 K1.274 m2 K

W

Walls U value: 0.78 W

m2 K

B. U factor Roof-CeilingThe estimation od the U value for roof-ceiling assembly is based on industry common standards as illustrated in fig-5, where and acceptable value is giver:

Uceiling = 0.20 W

m2 K


C = k/lTable 8.2 Textbook p.166 Ch26Fundamental

Table 4 Ch26.5ASHRAEFundamentals 2009

R = 1/C = l / k

Figure 5-Source: http://www.buildingscience.com/documents/reports/rr-0404-roof-design

C. U factor windowsFrom Table 1 ASHRAE Fundamentals 2009 Ch17.5

U : 2.53 W

m2 K (U-Factor) SHGC : 0.46 (Solar Heat Gain Coefficient)

1. Windows ScheduleThe type of windows installed in the apartment consists of clear double pane glass window with fiberglass/Vinyl operable frame.

Description Width (m) height (m) Perimeter (m) Area ( m2)Window-1 1.14 2 6.28 2.3Window-2 1.14 2 6.28 2.3Window-3 0.8 2.15 5.9 1.7Window-4 0.95 2 5.9 1.9Window-5 0.95 2 5.9 1.9Window-6 0.95 2 5.9 1.9Window-7 0.7 2 5.4 1.4Window-8 1.08 2 6.16 2.2Window-9 0.7 2 5.4 1.4Window-10 0.88 1.1 3.96 1.0

Total Perimeter Total Area57.1 m 17.9 m2


Table 2-Table 1 ASHRAE Fundamentals 2009 Ch17.5

D. InfiltrationInfiltration directly affects the heating and cooling loads. When air leakage is significant, it will be a continuous loss of energy either heating or cooling.

Using equations

(8) ASHRAE Fundamentals 2009 Ch17.5


The (Aul) unit leakage area, and ( IDF) infiltration driven force, are estimated using tables -3,4, and 5 from ASHRAE Fundamentals 2009 Ch17.6 . Note for the apartment in study H = 3m


Note: Building constructed in 1930

Table 3 - Tables-3,4,5 ASHRAE Fundamentals 2009 Ch17.5

We know from table:

Aes = Building exposed Area =

[ 156m2 – ( 13.06m 3m ) ] ≈117 m∙ 2

Aul = 5.6 cm2/m2 ; IDFHeating = 0.093 L/(s cm∙ 2) ; IDFCooling = 0.032 L/(s cm∙ 2)

Calculating the infiltration flow rate (Q i):

AL = 117 5.6 = 655.2 cm∙ 2

For Heating: Q i = 655.2 0.093 ≈ 61 L/s∙

Q i = 61 L/s (Heating)For Cooling: Q i = 655.2 0.032 ≈ 21 L/s∙

Q i = 21 L/s (Cooling)

E. VENTILATIONNo ventilation system is installed in the apartment neither the rest of the building. No calculations are performed.

F. COOLING LOAD

Cooling loads are estimated for sensible cooling load on 4 parameters: 1- opaque surfaces, 2-windows (Fenestration), 3-Infiltration and 4-Ocupancy. Latent load cooling load is evaluated apart.

1. Opaque SurfacesWall, floor and Ceiling and doors are considered as opaque surfaces. The load gains caused by the gradient temperature in air when moving across the listed surfaces and solar radiation received by the opaque surfaces.Using Equations:


qopq = A × CFopq (20) ASHRAE Fundamentals 2009 Ch17.8

CFopq = U(OFt Δt + OFb + OFrDR) (21) ASHRAE Fundamentals 2009 Ch17.8

From Table 7 ASHRAE Fundamentals 2009 Ch17.9, we find:

OFt : 1 ; Δt : (28.5oC-24 oC) = 4.5K ; OFb : 8.2 K ; OFr : -0.36


Table 4 - Table-7,8 ASHRAE Fundamentals 2009 Ch17.9

DR: 10.8 K (from Design conditions for MONTREAL MIRABEL AIRPORT, QC, Canada -Appendix)

U = 0.78W

m2 K ( This value was calculated in section IV.A of this report)

Calculating:

CFopq = 0.78 (1 4.5 + 8.2 - 0.36 10.8)∙ ∙ ∙

CFopq = 6.87 W/m2

Now to find A (net surface area for the opaque surfaces), we need to subtract the windows surface area from the total walls perimeter area, this values where estimated in section III.B

A: 156 m2– 17.9 m2 = 138.1 m2

Calculating opaque surface cooling load (W) :

qopq = 138.1 m2 6.87∙ W/m2 = 948.7 W

qopq ≈ 949 W ( opaque surface cooling load )

2. Transparent Fenestration SurfacesClear double pane glass window with fiberglass/Vinyl operable frame. Note: Door to balcony is considered as a window in the calculations (window-3).

The table below presents the window’s facing orientation:


Using Equations:

qfen = A × CFfen (24) ASHRAE Fundamentals 2009 Ch17.9

CFfen = U(Δt – 0.46DR) + PXI × SHGC × IAC × FFs (24) ASHRAE Ch17.9


IAC = 1 + Fcl (IACcl – 1) (29) ASHRAE Fundamentals 2009 Ch17.10

All necessary values are obtained from the ASHRAE Tables shown below: Table-13, Table-10, Table-11 in chapters 17.09-17.10 Fundamentals 2009


Windows have no shading, therefore only Eq.26 will be used to calculate PXI value.

Windows have no shading, therefore IAC=1

Description Width (m)

height (m)

Perimeter (m)

Area( m2 )

OrientationWindow facing:

Window-1 1.14 2 6.28 2.3 South /WestWindow-2 1.14 2 6.28 2.3 South/ EastWindow-3 0.8 2.15 5.9 1.7 South/ EastWindow-4 0.95 2 5.9 1.9 South/ EastWindow-5 0.95 2 5.9 1.9 NorthWindow-6 0.95 2 5.9 1.9 NorthWindow-7 0.7 2 5.4 1.4 North / EastWindow-8 1.08 2 6.16 2.2 NorthWindow-9 0.7 2 5.4 1.4 North/ WestWindow-10 0.88 1.1 3.96 1.0 South /West

Total Perimeter

Total Area

57.1 m 17.9 m2

From Table 1 ASHRAE Fundamentals 2009 Ch17.5

U : 2.53 W

m2 K (U-Factor) SHGC : 0.46 (Solar Heat Gain Coefficient)

Calculating for PXI value: (W/m2)


Now calculating for CFfen : in the following table all the values are summarized to facilitated calculations for each window.

Now the total qfen (W) the fenestration cooling load can be calculated using Eq.24 :

qfen = A × CFfen → qfen = 17.9 • 472 = 8,449 W

qfen = 8,449 W ( Cooling Load )


Total Area17.9 m2

3. Infiltration Load

q vi,s = Cs[Qvi + (1 – εs)Q bal, hr + Q bal, oth]Δt (15) ASHRAE Fundamentals 2009 Ch17.7

q vi, l = Cl (Qvi + Q bal,oth)ΔW (no HRV/ERV) (16) ASHRAE Fundamentals 2009 Ch17.7

As there is no ventilation involved, the equation 15 and 16 are simplified into:

q vi,s = Cs[Qvi + (1 – εs)Q bal, hr + Q bal, oth]Δt

q vi, l = Cl (Qvi + Q bal,oth)ΔW

And result same as Eq 1 and 2 :

qs = CsQΔt (1) ASHRAE Fundamentals 2009 Ch17.3

ql = ClQΔW (2) ASHRAE Fundamentals 2009 Ch17.3

We know:

Cs = 1.23 W/(L·s·K ) ; C l = 3010 W/ (L ·s ) ; Q i = 21 L/s (for Cooling) from in p.15.

Δt = 4.5 K ; ΔW = ( 0.0128 - 0.0094 ) = 0.0034 kgw/kgda


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Now calculating for sensible and latent infiltration load:

qs = 1.23 21 4.5 = 116.2 W∙ ∙

ql = 3010 21 0.0034 = 214.9 W∙ ∙

qs = 116 W (sensible infiltration load )

ql = 215 W ( latent infiltration load )

4. Internal GainsThis is the energy required by the presence of occupants, lighting, and appliances that all together produce a sensible and latent thermal load.

For the max and lower temperature design parameters this gains can be estimated using equations:

q ig,s = 136 + 2.2Acf + 22Noc (30) ASHRAE Fundamentals 2009 Ch17.10

q ig,l = 20 + 0.22Acf + 12Noc (31) ASHRAE Fundamentals 2009 Ch17.10

We know: Acf : 134 m2 ; Noc : 4 occupants

q ig,s = 136 + 2.2∙ 134 + 22∙ 4 ≈ 519 W

q ig,l = 20 + 0.22∙ 134 + 12∙ 4 ≈ 97 W

q ig,s = 519 W ( sensible internal gains -cooling load )

q ig,l = 97 W ( latent internal gains- cooling load)


5. TOTAL COOLING LOADSIn the previous calculations the components of the cooling load where estimated, 1- opaque surfaces, 2-windows (Fenestration), 3-Infiltration and 4-Ocupancy. Latent load cooling loads where evaluated individually.

The Total cooling load is calculated using equation:

qt = qs + ql (4) ASHRAE Fundamentals 2009 Ch17.3

qs, ql, qt = sensible, latent, total heat transfer rates, W

For the apartment in study, the Total sensible and latent cooling load is calculated:

qs = qwalls + qwindows + q sensible infiltration + q sensible internal gains

ql = q latent infiltration + q latent internal gains

Calculating:

qs = ( 949 W + 8,449 W + 116 W + 519 W ) = 10,033 W

ql = ( 215 W + 97 W ) = 312 W

qs = 11,827 W (Total sensible cooling load)

ql = 312 W (Total latent cooling load)

Calculating Total cooling load : qt = qs + ql

qt = 10,033 W + 312 W = 10,345 W

qt = 10,345 W (Total cooling load)


G. HEATING LOAD

Calculations are performed for the maximum heat loss by blocks. The RLF Method takes conservative assumptions in the estimations, considering that there is no solar gains, neither internal gains, and also the building heat storage also is ignored. Then calculations are simplified into a steady-state analysis.

1. Exterior Surfaces Above Grade (walls, doors, ceilings or windows)

Surfaces exposed to exterior conditions, such as walls, doors, ceilings or windows. Energy load is estimated using:

q = A × HF (33) ASHRAE Fundamentals 2009 Ch17.3

HF = UΔt (34) ASHRAE Fundamentals 2009 Ch17.3

Combining Eq. 33 and 34 a simplified equation is obtained:

q = A U Δt∙ ∙We know:

A wall = 99.1 m2 ; Aceiling = 134 m2 ; Awindows = 17.9 m2 ; Δt = 20 oC –(-21.1 oC) = 41.2 K

U walls = 0.78 W

m2 K ; Uceiling = 0.20

W

m2 K ; Uwindow = 2.53

W

m2 K

Now calculating for walls, ceilings and windows:

qwalls = 99.1 0.78 41.20 = 3,184.6 W∙ ∙

q ceiling = 134 0.20 41.20 = 1,104.2 W∙ ∙

qwindow = 17.9 2.53 41.20 = 1,865.8 W∙ ∙


http://www.sedgemoor.gov.uk/CHttpHandler.ashx?id=2635&p=0

Note: window area is subtracted from exposed wall area

http://www.sedgemoor.gov.uk/CHttpHandler.ashx?id=2635&p=0

2. Ventilation and Infiltration

Infiltration is estimated for sensible load, consisted in the energy necessary to heat the infiltrated is flow to inside room temperature. Also infiltration latent heat load is estimated to quantify the energy required by moisture loss. The infiltration rate flow Q of outdoor air entering the apartment is estimated as described in the Common Data and Procedures section of ASHRAE Fundamentals 2009 Ch17.5

q vi,s = Cs[Qvi + (1 – εs)Q bal, hr + Q bal, oth]Δt (15) ASHRAE Fundamentals 2009 Ch17.7

q vi, l = Cl (Qvi + Q bal,oth)ΔW (no HRV/ERV) (16) ASHRAE Fundamentals 2009 Ch17.7

As there is no ventilation involved, the equation 15 and 16 are simplified into:

q vi,s = Cs[Qvi + (1 – εs)Q bal, hr + Q bal, oth]Δt

q vi, l = Cl (Qvi + Q bal,oth)ΔW

And result same as Eq 1 and 2 :

qs = CsQΔt (1) ASHRAE Fundamentals 2009 Ch17.3

ql = ClQΔW (2) ASHRAE Fundamentals 2009 Ch17.3


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We know:

Cs = 1.23 W/(L·s·K ) ; C l = 3010 W/ (L ·s ) ; Q i = 61 L/s (for Heating) from p.15.

Δt = 20 oC –(-21.1 oC) = 41.2 K ; ΔW = ( 0.0045 - 0.0002913 ) = 0.00421 kgw/kgda

Now calculating for sensible and latent infiltration load:

qs = 1.23 61 41.2 = 3,091.2 W∙ ∙

ql = 3010 61 0.00421 = 772.99 W∙ ∙

qs = 3,091 W (sensible infiltration load )

ql = 773 W ( latent infiltration load )

3. TOTAL HEATING LOADS

In the previous calculations the components for the Heating load where estimated, 1)- Exterior Surfaces (that includes walls, doors, ceilings and windows) and 2)-Infiltration, where Latent heating loads where evaluated individually. As mentioned before assumptions for the RLF Method consider that there is no solar gains, neither internal gains and that the building heat storage also is ignored. Then calculations are simplified into a steady-state analysis.

The Total heating load is calculated using equation:

qt = qs + ql (4) ASHRAE Fundamentals 2009 Ch17.3

qs, ql, qt = sensible, latent, total heat transfer rates, W

For the apartment in study, the Total sensible and latent heating load is calculated:


qs = qwalls + qceiling + qwindow + q sensible infiltration + q sensible internal gains

ql = q latent infiltration + q latent internal gains

Calculating:

qs = (3,184.6 W + 1,104.2 W + 1,865.8 W + 3,091 W + 0 W ) =9,245.6 W

ql = ( 773W + 0 W ) = 773 W

qs = 9, 246 W (Total sensible heating load)

ql = 773 W (Total latent heating load)

Calculating Total cooling load : qt = qs + ql

qt = = 9, 246 W + 773W = 10, 019 W

qt = 10, 019 W (Total Heating load)


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V. eQUEST Simulation

QUEST software is a simple energy analysis tool, designed to be use by any designer with very simple entry parameters and yet with the capability to deliver professional results.

Using the friendly Schematic Design Wizard user interface, the software guides step by step to input the parameters required.

A. Design input ParametersThe most relevant parameters used to run the software are presented in the following table:

Description Input value

Building Type Multifamily-Low RiseTotal Apartment area (134 m2) x 2 2884 ft2

Location Montreal, QCWall Assembly 0.78 W/(m2 K)∙Roof-Ceiling Assembly 0.20 W/(m2 K)∙Windows 2.53 W/(m2 K)∙Window Area 17.9 m2

SHGC (Solar Heat Gain Coefficient) windows 0.46Exterior Doors 1Occupancy Entire Year, 24hrs Typical UseHeating System Electric BaseboardCooling Indoors Temperature Occupied 24 oC (75 oF)Cooling Indoors Temperature Unoccupied 26 oC (79 oF)Heating Indoors Temperature 20 oC (68 oF)Heating Indoors Temperature Unoccupied 15 oC (59 oF)Electric Water Heater 58Gal 4500W / 220VElectricity Utility Charges < 1860 kW $0.06404/kWhElectricity Utility Charges > 1860 kW $0.09497/kWhElectricity Utility Charges/ Costumer Charge $30.36/month


B. Tables

1. Annual heating and cooling loads

What are your annual heating and cooling loads………….??????

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VI.REFERENCES


building science final project

Documents

cooling factor

comfort cooling heating

building data11iv

rlf method

building location source

cooling load161

cooling results

simplified method