Stefko, J, 1998, Technical University Zvolen

Background

Actual structures of wooden family houses enable to increase the energy consumption but in the other
hand mean the risk of impairment of indoor quality. Light opaque structures are especially sensible to
excessive thermal gains in the summer time. Dynamic simulation methods enable to predict the indoor quality as well as the energy consumption and to influence them in the design process p. e. by the configuration of building or control devices.

Project

Technical University Zvolen - Departement of Wooden Structures collaborates with BUCINA on the project of wooden family houses. There should be presented the utilizing of simulation in esp-r program
on the realized examples of houses.

1. Analysis of energy consumption and indoor quality of wooden family house.

Simulation is presented on the model of wooden family house (fig.1)

FIG. 1: Views

A multizone model of building respecting the position of the rooms was made in esp-r manager. Thermal proprieties of enclosure structures are in Tab. 1.

FIG. 2: Multizonal model of building in esp-r manager

TAB. 1: Thermal proprieties of enclosed structures
 

NO.	Structure	u-value [W/m2/K}
1.	Walls	0.22
2.	Windows	1.7
3.	Roof	0.18
4.	Ceiling	0.18
5.	Floor	0.35

There were simulated air exchange 0.8 /hour and thermostatically controlled heating. Reference year were selected as characteristic for Slovak region.

Step 1: Simulation of model with ideal control in heating season minimal 20 grad. C.

Energy consumption values are in Tab. 2

TAB 2: Energy consumption simulated in step 1:
 

Zona (SK)	Zone (Eng)	Energy required	Heating time
detska	Child	1378.7	4965
fitnes	Fitness	485.5	3606
hala	Staircase	127.4	1600
izba	Room	1110.7	4341
kuchyna	Kitchen	2272.4	4479
kupelna	Bathroom	703.0	4141
obyvacka	Living room	1841.2	4010
pracovna	Master room	1445.7	5305
spalna	Bedroom	1103.7	4592
	Total	10468.3

Step 2: Interrupted thermostatically controlled heating.

Setting the thermostat to value in night min. 15 grad. C led to unacceptable indoor climate. Acceptable climate in simulated model should be ensured only by regulation thermostat to value 17.5 grad. C in night time.

FIG. 3: Time-var. graph of indoor temperature in zone "Living room" in heating period with
           interrupted heating

2. Analysis of indoor quality in summer time

There are values of indoor temperature in july presented at Fig. 4 that indicate the extreme impairment of indoor quality in summer time in extreme positioned zone "Living room" caused by redundant solar gains
and low accumulation of light structures

FIG. 4: Time-var. graph of indoor temperature in zone "Living room" in hottest july days

Implementation of control devices (shading by shutter) and higher air exchange on the model enabled to
increase the indoor temperature to acceptable values presented at Fig. 5

FIG. 4: Time-var. graph of indoor temperature in zone "Living room" in hottest july days - model
with shutters and air exchange 0.8 - 2.0 /hour (function represented opening and shutting the windows).

For more information Stefko, J, Technical University Zvolen