In-Situ Performance Evaluation of Spray Polyurethane Foam in the Exterior Insulation Basement

Assessing Heat Flow Patterns in Basement Walls with Exterior Insulation

Michael Swinton1, Wahid Maref,2 Mark Bomberg3, Kumar Kumaran4 and Nicole Normandin5

Abstract

Most studies on thermal performance of basement construction systems have focussed on modelling. There has been lack of detailed monitored performance data to substantiate the models. Therefore, a joint research project6 of industry and the Institute for Research in Construction was initiated to assess the in-situ thermal performance of a number of insulation products used as exterior basement insulation. The effect of two- year monitoring provided an opportunity to analyze in detail the heat flow patterns in two experimental walls, each having 8 insulation specimens instrumented side-by-side. The paper presents the key findings on both the experimental and analytical side. A number of analytic tools ( 2-D and 3-D analyses) were developed to interpret the temperature fields in detail. As a result, a clearer picture of two and three dimensional heat flow patterns within the basement walls was developed. The analysis provided in this paper deals with heat flow through the exterior insulation below ground, as well as vertical and lateral components of heat loss, and thermal storage effects in the concrete wall. With this information, the authors can differentiate between the thermal performance of the wall system and that of the insulation materials themselves.

Keywords: Heat transfer, insulation, thermal resistance, measurement, storage, temperature, heat loss.

1 Mr. M.C. Swinton is a Senior Research Officer at the Institute for Research in Construction (IRC), National Research Council of Canada (NRCC), Ottawa, Ontario, Canada. 2 Dr. W. Maref is a Research Officer at the IRC/NRCC. 3 Dr. M.T. Bomberg is a Senior Research Officer at the IRC/NRCC. 4 Dr. M.K. Kumaran is a Senior Research Officer at the IRC/NRCC. 5 M. N. Normandin is a Technical Officer at the IRC/NRCC. 6 The consortium included Canadian Plastics Industry Association, Expanded Polystyrene Association of Canada, Canadian Urethane Foam Contractors Association, Owens Corning Inc. and Roxul Inc.

1 Assessing Heat Flow Patterns in Basement Walls with Exterior Insulation

Michael Swinton, Wahid Maref, Mark Bomberg, Kumar Kumaran and Nicole Normandin

Abstract

Most studies on thermal performance of basement construction systems have focussed on modelling. There has been lack of detailed monitored performance data to substantiate the models. Therefore, a joint research project6 of industry and the Institute for Research in Construction was initiated to assess the in-situ thermal performance of a number of insulation products used as exterior basement insulation. The effect of two- year monitoring provided an opportunity to analyze in detail the heat flow patterns in two experimental walls, each having 8 insulation specimens instrumented side-by-side.

The paper presents the key findings on both the experimental and analytical side. A number of analytic tools ( 2-D and 3-D analyses) were developed to interpret the temperature fields in detail. As a result, a clearer picture of two and three dimensional heat flow patterns within the basement walls was developed. The analysis provided in this paper deals with heat flow through the exterior insulation below ground, as well as vertical and lateral components of heat loss, and thermal storage effects in the concrete wall.

With this information, the authors can differentiate between the thermal performance of the wall system and that of the insulation materials themselves.

2 INTRODUCTION

In Canada, the basement has become a part habitable living space. Combined with requirements in energy conservation, this has prompted development of insulated basement systems. Some of these systems use thermal insulation on the exterior of the basement wall. In addition to reducing heat loss, external insulation may also have a significant effect on the moisture performance and durability of the basement envelope system.

The need to protect the foundation from the below-grade environment is not a new concept (Crocker, 1961, Elmorth, 1975, Crocker, 1974, Bomberg, 1978, Timusk

1981 and Hutcheon, 1963). Over the years, new products and systems have been introduced to perform this function. How these new materials actually perform and whether or not they can meet the performance requirements for basements were key issues addressed by those responsible for developing regulations governing their use in

Canadian construction.

Previous papers by Sterling (Sterling, 1986) and Nelson (Nelson, 1989) to establish the suitability of insulation products for below-ground application mainly through the laboratory measurements of properties after exposure. Little information was available on the in-situ thermal performance nor on the performance of insulation products exposed unprotected in belowground applications.

In this context, the Canadian thermal insulation industry, working together with the National Research Council, decided to revisit (see Tao et al, 1980 and Bomberg,

1980) the design and performance of external insulation basement systems (EIBS).

3 PART 1. PROJECT DEFINITION

1.1 Objectives

This research project involved a number of material and system issues. Material considerations involved the selection of existing and new thermal insulation products

(being under development). These products were placed side-by-side on the basement wall to create virtual test compartments. The insulation was exposed to the Ottawa climate, including below-grade conditions, over a two and half-year period from October

1995 to June 1998. Over this period, ten expanded polystyrene (EPS), two spray polyurethane foam (SPF), two mineral fibre insulation (MFI) and two glass fibre insulation (GFI) specimens were placed on the exterior of the basement wall in the experimental building located on NRC Campus in Ottawa.

1.2. Experimental

To evaluate performance of exterior basement insulation, different materials were installed on the exterior surface of concrete basement walls. As shown in Figure 1, eight test specimens were placed side-by-side, on each of two basement walls (east and west) insulating a whole wall with approximately 2.99-in (76-mm) thick and 7.87-ft (2.4-m) high specimens. On the interior of the wall, a 0.98-in (25-mm) layer of expanded polystyrene (EPS) board was installed over the entire surface. At 3 vertical locations on each test wall, cut-outs were made and calibrated EPS specimens, with identical thickness, were tightly inserted. These specimens were used for determination of transient heat flux entering the wall (Bomberg et al, 1994).

4 Thermocouples were placed at the boundary surfaces as well as the interfaces of each layer in the wall, in an array consisting of 16 points per tested compartment. All sensors placed on the west wall are shown in Figure 2.

The parameters monitored in the EIBS are:

1. Surface temperatures, on both sides of the calibrated specimen, the concrete and

the test specimens

2. Heat flux across the calibrated insulation specimens

3. Soil temperatures from 3.28-ft (1-m) to 6.56-ft (2-m) away from the specimens,

and at 5 depths

4. Interior basement air temperature (average of 4 readings)

5. Exterior air temperature (at north face, shielded from sun)

6. Relative humidity (RH) and other parameters of indoor and outdoor

environments.

The instrumentation package consisted of approximately 145 thermocouples, 2 humidity sensors, 21 calibrated insulation specimens (heat flux transducers), 4 junction boxes, and a data acquisition unit operated by a computer.

1.2.1. Indoor and Outdoor Air Temperature Profiles

The indoor and outdoor air temperature profiles over the two heating seasons are shown in Figure 3 Data was recorded every half-hour. Plotted is every 8th reading, i.e., every 4 hours.

The indoor basement air temperature was held relatively steady at 73.4F (23°C), with some loss of control experienced in the shoulder seasons. The switch from heating

5 to air-conditioning on the heat pump was manual, resulting in slight overheating of the basement on warm days in spring and fall when the heat pump was set to heating.

The outdoor temperatures show both the diurnal variations and seasonal trends following a rough sine wave. The winter of 1997 featured one very cold night only, with temperatures dipping to about -22F (-30°C). Neither winters showed a sustained cold snap – each very cold evening was often followed by a thaw (temperatures climbing above 32F (0°C)). This unexpected weather pattern may have resulted in low frost penetration, as documented further in the report.

1.2.2. Soil Temperatures

Soil temperatures were measured at a distance of 6.56-ft (2-m) from the wall.

The results for the instrument set nearest specimen W6 are shown for three depths in

Figure 4. These were measured at 5.91-in (150-mm), 29.1- in (740-mm) and 72.44-in

(1840-mm) below-grade, over two-year period. The sensors nearer the soil surface shows the greatest variation form summer to winter, and diurnal effects can be observed. No diurnal effects can be seen at the two lower depths. The temperatures at the lowest depth approximate a sine wave each year.

It should be noted that in both winters, the frost penetrated approximately 5.91-in

(150-mm). The frost depth temporarily reached 10.63-in (270-mm) in the second winter

(not shown in graph). Deep snow cover and repeated thaws in both heating seasons may be the cause of shallow frost penetration. An independent temperature measurement in the second winter, 32.81-ft (10 m) from the house showed the same result. This indicates that there is an undetectable effect because of basement heat loss on the soil temperature at 6.56-ft (2 m) from the house.

6 1.2.3. Temperatures through the Wall System

Figure 5 shows measured temperatures of indoor air, calibrated insulation specimens, concrete, and soil surface in the “mid-position” of the wall over a period of two years. The spikes in the interface between soil and the EIBS correspond to thaw periods with a heavy rainfall. Observe that these effects do not appear to affect the temperature on the concrete surface, i.e., behind the external insulation.

1.2.4. Method to Measure Thermal Resistance In Situ

A test method, developed at NRC during previous project (Muzychka, 1992;

Bomberg and Kumaran 1994), involves testing two materials placed in contact with each other - a reference material whose thermal conductivity and specific heat are known as a function of temperature, and a test specimen whose thermal properties are unknown.

Because of its comparative character, this method has been called a heat flow comparator

(HFC). In a previous experiment involving roof insulation, the reference and tested specimens were placed in the exposure box representing a conventional roofing assembly. Thermocouples were placed on each surface of the standard and reference materials to measure temperatures, which then were used as the boundary conditions in the heat flow calculations.

The heat flux across the boundary surface between reference and tested specimen is calculated using a numerical algorithm to solve the heat transfer equation through the reference material. Imposing the requirement of heat flux continuity at the contact boundary between test and reference materials, corresponding values of thermal conductivity and heat capacity of the tested specimens are found with an iterative

7 technique. Performing these calculations for each subsequent data averaging period will result in a set of thermal properties of the test material which, over the period of measurements, give the best match with its boundary conditions (temperatures and heat flux).

Since thermal conductivity of the specimen is a function of its temperature, the solution of the heat transfer equation is based on central finite difference calculations that include Kirchoff's potential function (integral of thermal conductivity over the range of temperature) and uses a Taylor's series to calculate heat flux through the surface.

Subsequent developments improved the stability of the numerical solution and produced a user friendly computer code that includes optimization routines. This method was documented and applied for determining the in-situ thermal resistance of roof insulation

(Bomberg and Kumaran, 1994).

PART 2. USE OF MODELS TO EXAMINE MEASURED RESULTS

Examination of preliminary results highlighted difficulties in establishing the precision of thermal testing without addressing 3-D effects. This is best illustrated by comparing two different product installed side-by-side tested wall sections (see Maref and al, 2001). The difference between one-dimensional estimate and the measured results is significant. This difference highlights the need for 3-D model application.

To evaluate effects of lateral heat flow on the precision of the field measurements, a new task was added to the Exterior Insulation Basement Systems (EIBS) project, namely development of a 3-D model. The first question was then, how to discretise the

8 continuous equations to arrive at the system, which is easy to solve with numerical techniques (see Maref and al, 2001).

2.1. Differences Between 2-D and 3-D Models

2-D finite difference analysis was developed by Swinton (Swinton et al, 1999).

This 2-D analysis consisted of calculating the horizontal (inside to outside) and vertical heat fluxes (bottom to top) through all materials in the control volume. A finite difference technique was used to solve the heat transfer equations for each point of a nodal network within the control volume.

More elaborate method was developed to assess the heat loss in the third dimension, along the wall, and to suggest what corrections were needed for the 2-D results (see Maref et al, 2001).

Maref et al (2001) calculated the average thermal resistance of specimens during a period in which one-directional heat flow is prevailing (days 510 to 660). The yearly difference between results obtained from 2-D and 3-D models was about four percentage points.

Application of this model permit better assessment of the average thermal resistance of the thermal insulating systems used in the study. The agreement between measured and calculated spatial and temporal temperature distributions were acceptable through the heating season. This benchmarking of the model gives a degree of confidence when evaluating the effect of the lateral heat flow.

9 2.2. Measured Vertical Heat Flux Profiles

Temperature differences across the thermally calibrated insulation layer at the inner face of the wall were calculated at 4 vertical locations with thermocouple and three vertical locations with heat flux meters shown in Figure 2.

Example profiles of heat flux into the basement wall are shown in Figure 6. The smoothness or regularity of these curves attests to the fact that the seven vertical readings are consistent with another one. These weekly averaged heat flux profiles have the highest level of accuracy associated with them. Each heat flux meter reading is the result of the average of 5 EMF readings.

2.3. Direction of the Heat Flow within the Wall

One of the key findings of the 2-dimensional analysis was that the concrete layer, which was effectively sandwiched between the exterior insulation specimens and the interior calibrated insulation board, created a significant confounding effect in heat loss patterns. Because the soil temperatures are coldest near the ground surface in the winter time, the concrete is also coldest in the upper portion of the wall, and heat tends to flow upward as well as outward. The resulting heat flux vector is at an angle that is rarely 0

(i.e. rarely horizontal). The analysis was used to produce plots of these heat flux angles, at various heights in the wall as a function of time over the monitoring period, as shown in Figure 7. It can be seen from the figure that the heat flux angle can vary from almost

60° in the upper wall to –60° at the bottom. Thus a considerable portion of the heat flux of the order of 20% actually by-passed the insulation specimens below grade, going into the footing and up the wall above grade and  10% can be stored in and released from the concrete. (Note, the horizontal component of heat flux goes to zero and slightly negative

10 in the high portions of the below grade wall in the summer resulting in alternately in angles +/- 90°, as the horizontal heat flux moves slightly on either side of zero. This is not significant, but is prominent in the graph).

2.4. Lateral Heat Flow Calculation

Over the course of the 2-dimensional analysis, it was noted that the temperature of the concrete (behind the specimens) differed from specimen to specimen. This raised the possibility that heat could flow through the concrete from one specimen to another, resulting in possible uncertainty in the orders of magnitude of performance assessed using the 2-dimensional analysis.

In response to this, a detailed 3-dimensional heat transfer analysis of the both the east wall and the west wall was undertaken. The same control volume used for the 2-D model

(Swinton et al, 1999) was used for the 3-D analysis, but this was extended in the third dimension along the wall, to encompass all specimens. The objective of this much more detailed analysis was to determine the order of magnitude of lateral heat flow in the concrete from one specimen to another, and to provide a correction on the 2-dimensional results for in-situ R-value of each specimen, where needed.

To illustrate the result of this analysis, an example result is shown in Figure 8 for the west wall. The angle between the actual heat flux vector and the normal direction is defined here as the heat flux angle; e.g. a zero angle denotes heat flux normal to the wall - no lateral heat flow.

The heat flow angle is plotted for the ‘top’ location (top of the control volume) in the concrete, at one point in time. A positive angle means lateral heat flow towards one end of the wall, and a negative heat flow means lateral heat flow towards the other.

11 The significance of this diagram is as follows. If the flow angle in the concrete behind the specimen is small, and in the same direction, then the lateral heat flow has little effect on the results. This was the case for W2, W3, W4, W5 and W8. On the other hand, specimen W6 appears to have been affected by significant lateral heat flow. Starting at the centre of the specimen, the heat flow on the south side is flowing south and the heat flow on the north side is flowing north. This is thus a lateral heat drain from the specimen, causing us to underestimate its thermal performance in the 2-D analysis. With this lateral flow, specimen W7 is gaining heat from W6, but is not passing this onto W8. The 2-D analysis would overestimate its performance for this point in time, at this vertical location of the specimen.

These lateral heat flows varied according to vertical position in the specimen and with time. The results were thus integrated over full height of the specimen and over each of two heating seasons. The 3-D analysis thus confirmed the order of magnitude of performance for specimens W2, W3, W4, W5, W7 and W8. The lateral heat flows affected specimen W6 in a significant way. The 3-D analysis showed better thermal performance of the W6 specimen in than the 2-D analysis by about 10%. Maref and al. (Maref, et al. 2001) have published details of the 3-dimensional analysis.

2.5. 2D & 3D In Situ Thermal Resistance Results

Figures 9, 10 show the resulting thermal performance plots for the specimen W5 for the first heating season and the second heating season respectively. Those figures show the comparison between the 2-D and the 3-D thermal performance. For the 2-D the change in thermal resistance adjustment is shown on a weekly basis over the two heating

12 seasons. The benchmark (100%) is the laboratory determined, initial value of thermal resistance of the specimen.

For the first heating season the difference between the 2-D and the 3-D analysis on the average relative R-value is around 2%. For the second heating season the difference is negligible.

The Figure 8 showed that the flow angle in the concrete behind the specimen is small, and in the same direction, then the lateral heat flow has no effect on the results. It means that 2-D gives the same analysis then the 3-D and for this reason the difference between the 2-D and the 3-D is small.

Figures 11, 12 show the resulting thermal performance plots for the specimen W6 for the first heating season and the second heating season respectively. Those figures show the comparison between the 2-D and the 3-D thermal performance. For the 2-D the change in thermal resistance adjustment is shown on a weekly basis over the two heating seasons.

The difference on the average relative R-value between the 2-D and the 3-D is around 9% for the first heating season and 7% for the second one. This means that for this specimen that the 2-D analysis under estimate the thermal performance during the two years about 8%.

A general analysis or observations on Figures 9, 10, 11 and 12 are as follows:

 all specimens show relatively steady performance through the heating seasons

 the second heating season show equal or improved performance for all specimens.

 Major rain and thaw periods (shown in Figure 3) do not appear to significantly affect

 the thermal performance of the specimens during these episodes.

13 3. DISCUSSION

The following general observations are made as a result of these experiments.

1. 2-D and 3-D analyses of the heat flow patterns in the wall were necessary to establish

the role of the exterior thermal insulation in controlling heat transfer in the

experimental wall.

2. The in-situ tracking of thermal performance of the specimens indicated relatively

stable thermal performance over the two years of monitoring. There was an

improvement in specimen thermal performance in the second heating season. This

correlates with dryer prevailing soil conditions in the second year. It also correlates

with observed shrinking of the clay soil as it dried, likely resulting in less

compression of the semi-rigid boards.

3. Based on the temperature profiles at the specimen/soil interface, and corresponding

observations of heavy rainfall or thaw periods, the specimens are apparently ‘handling’

moving water at the specimen surface.

4. CONCLUDING REMARKS

For the conditions recorded over the two-year monitoring period in this experiment, the insulation specimens showed stable thermal performance in the soil, with each of the specimens showing only small variations from its average value (see Swinton and al., CTU). This performance was sustained even during major rain storms and winter thaws, when the effects of water movement was recorded at the outer face of the

14 insulation specimens — contrary to expectations that the R-value would decline under such circumstances, especially if water were to move through the insulation.

To evaluate the effect of lateral heat flow in concrete behind the different insulation products involved in this project with a different thermal resistance one, a 3-D model was necessary.

This study has shown the advantages given by the 2-D analysis and its limitations to evaluate the lateral heat flow. The 3-D analysis has given better assessment of this flow and of the long-term thermal resistance of the thermal insulating systems used in this study.

The 3-D analysis thus confirmed the order of magnitude of performance for specimens W2, W3, W4, W5, W7 and W8. The lateral heat flows affected specimen W6 in a significant way. The 3-D analysis showed better thermal performance of the W6 specimen in than the 2-D analysis by about 9 %.

This study has shown the importance of the 3-D analysis for increasing the confidence in estimating the effect of the lateral heat flow significantly.

ACKNOWLEDGEMENT

Deep gratitude and thanks are forwarded to Roger Marchand who installed the data acquisition system and John Lackey for his contribution in the experimental work.

15 REFERENCES

Crocker, C.R. 1961. House Basements, Canadian Building Digest No. 13, National Research Council of Canada, Division of Building Research, Ottawa, 1961 (Amended 1974), 4 p.

Elmorth, A. and Holglund, I. 1971. New basement wall designs for below-grade living space. Originally published in Stockholm, 1971. Technical translation prepared for National Research Council, Division of Building Research, Ottawa, 1975.

Crocker, C.R. 1974. Example Result: Moisture and Thermal Considerations in Basement Walls, Canadian Building Digest No. 161, National Research Council of Canada, Division of Building Research, Ottawa, 1974, 4 p.

Bomberg, M.T. 1978. Some performance aspects of glass fiber insulation on the outside of basement walls, Symposium on Thermal Insulation Performance, Tampa, FL 1978, ASTM Special Technical Publication, vol. 718, 1980, pp. 77-91.

Timusk, J. 1981. Insulation retrofit of masonry basements, Report for the Ministry of Municipal Affairs and Housing, Ontario, Oct. 1981, ISBN 0-7743-7052-1.

Hutcheon, N.B. 1963. Requirements for exterior walls, Canadian Building Digest No. 48, National Research Council of Canada, Division of Building Research, Ottawa, 1963, 4 p.

Sterling, R.L., 1986. “Moisture Absorption and its Effect on the Thermal Properties of EPS Insulation for Foundation Applications”. Contract report by Underground Space Center, University of Minnesota, October, 1996.

Nelson, B.D., 1989. “Conditions of a Sample of Minnesota Exterior Foundation Wall Insulation Materials”. Conference proceedings of Thermal Performance of Exterior Envelopes of Buildings IV, ASHRAE/DOE/BTECC/CIBSE. Dec 4-7, 1989.

Tao, S.S.; Bomberg, M.T.; Hamilton, J.J., 1980. Glass fiber as insulation and drainage layer on exterior of basement walls, Symposium on Thermal Insulation Performance, Tampa, FL, USA, 1978, pp. 57-76, ASTM Special Technical Publication, vol. 718 (NRCC-19317)

Bomberg, M.T. 1980. Some performance aspects of glass fiber insulation on the outside of basement walls, Symposium on Thermal Insulation Performance, Tampa, FL 1978, ASTM Special Technical Publication, vol. 718, 1980, pp. 77-91.

Bomberg M.T., Y.S. Muzychka, D.G. Stevens and M.K. Kumaran, 1994. A comparative test method to determine thermal resistance under field conditions, J. Thermal Insul. and Bldg. Envs., Vol 18, Oct 1994, pp.

16 Muzychka Y., 1992. A method to estimate thermal resistance under field conditions. NRC/IRC internal report No 638, Dec. 1992.

Bomberg M.T. and Kumaran M.K., 1994. Laboratory and roofing exposures of cellular plastic insulation to verify a model of aging. Roofing Research and Standards Development, ASTM STP 1224, T. J. Wallace and W. J. Rossiter, Jr., Eds., American Society for Testing and Materials, Philadelphia.

Maref, W., Swinton, M.C., Kumaran, M.K., Bomberg, M.T., 2001. 3-D analysis of thermal resistance of exterior basement insulation systems (EIBS). Journal of Building and Environment Vol. 36, No 4, PP. 407-419, 2001 (NRCC-43090)

Swinton M.C., Bomberg M.T., Kumaran M.K. and Maref W., 1999. In situ Performance of Expanded Polystyrene in the Exterior Basement Systems (EIBS). Journal of Thermal Env. & Bldg. Sci. Vol. 23 - October, 1999.

Swinton, M.C., Bomberg, M.T., Kumaran, M.K., Maref, W. 2000. Performance of Thermal Insulation on the Exterior of Basement Walls", Construction Technology Update, Institute for Research in Construction, NRCC. N36 (NRCC-43678)

17 TABLE OF FIGURES

Figure 1. Schematic of placement of specimens on the West wall.

Figure 2. Thermocouples and calibrated insulation specimens on the West wall.

Figure 3. Temperatures across the W6 specimen measured in the mid-height position.

Figure 4. Indoor and Outdoor Temperature profile over the Monitoring Period.

Figure 5. Soil temperature profiles over the monitoring period.

Figure 6. Typical profiles of heat flux through the reference insulation at the inner face of the wall.

Figure 7. Direction of heat flux in the wall over the monitoring period.

Figure 8. Angle of heat flux vector calculated at the top position of the west wall. Positive sign indicates the lateral flow in the Northward direction.

Figure 9. Comparison of relative R-Value under field conditions on the West wall over the first heating season for specimen W5 (2D and 3D).

Figure 10. Comparison of relative R-Value under field conditions on the West wall over the second heating season for specimen W5 (2D and 3D).

Figure 11. Comparison of relative R-Value under field conditions on the West wall over the first heating season for specimen W6 (2D and 3D).

Figure 12. Comparison of relative R-Value under field conditions on the West wall over the second heating season for specimen W6 (2D and 3D).

18 19 West Wall

Thermocouples m m

in soil 0 4 m 2 m m

5 0 1 7 m 2

m 4 Thermocouples

0 4 m 7 Heat flux transducer

m (average of 5 emf's)

0 4 m 3 4 Thermocouples 1 m

4 Heat flux transducer 8 (average of 5 emf's) 1

4 Thermocouples

Soil thermocouples 1980 mm from wall at top 1370 mm from wall at bot. Heat flux transducer (locations approx.) (average of 5 emf's)

4 Thermocouples

200 mm

20 Indoor and Outdoor Air Temperatures

EIBS - Monitoring Results June 5, 1996 - June 8, 1998 40

20 ) C ° (

10 e r u t a r e p

m 0 e T

-30 0 30 60 90 120 150 180 210 240 270 300 330 360 390 420 450 480 510 540 570 600 630 660 690 720 750 June 5/96 Oct 3/96 Jan 1/97 Apr 1 May 31 Aug 29 Oct 28 Dec 27 Feb 25/98 May 26 Time (days from start)

21 Soil Temperatures Adjacent to Sample W6

EIBS - Monitoring Results June 5, 1996 - June 8, 1998 25

15 1840 mm from grade C ° e r u t a 10 r e p m e T 150 mm 740 mm from grade 5 from grade

0 0 30 60 90 120 150 180 210 240 270 300 330 360 390 420 450 480 510 540 570 600 630 660 690 720 750 June 5/96 Oct 3 Jan 1/97 Apr 1 May 31 Aug 29 Oct 28 Dec 27 Feb 25/98 May 26

-5 Time (Days from June 5, 1996)

Indoor AIr

Reference Insulation ) C ( Concrete e 15 r u t a r e p Specimen m e

5 Soil

0 0 30 60 90 120 150 180 210 240 270 300 330 360 390 420 450 480 510 540 570 600 630 660 690 720 750 780 June 5/96 Oct 3/96 Jan 1/97 Apr 1 May 31 Jul 30 Sep 28 Nov 27 Jan 26/98 Apr 26 June 25 Days from Start

23 Example Heat Flux Profiles Into the Basement Wall For October 1996, January and June 1997

1800 October June January 1600 )

m 1400 m ( b a l

S 1200 m o r f

e 1000 c n a t s i

D 800 l a c i t r

e 600 V (Heat flux measured 400 in this direction)

0 0 1 2 3 4 5 6 7 8 9 10 Heat Flux (W/m2)

24 Direction of Heat Flux In the Wall Start = 6/5/96 West Wall - Specimen w6 100

80 m o r High f

60 s e e r 40 ) g l e a t D

( 20 n

l Middle z i g r 0 n o A h

x -20 u Low l F

t -40 a e

H -60 Bottom -80 120 150 180 210 240 270 300 330 360 390 420 450 480 510 540 570 600 630 660 690 720 750 780 Jan 1, '97 Apr 1 May 31 Oct 3, '96 Days

25 3-D Analysis 40 South North (Jan 17, 1997) 30 ) C ° (

X 20 W8 W7 W6 W5 W4 W3 W2 Z r o t 10 c e v x

u 0 l f t 0 1 2 3 4 5 6 a e -10 h f o e l -20 g n A -30 Angle at the internal surface Angle inside of the concrete layer Series1 -40 Series2 Series1Distance Z (m) Series1 Series1 Series1 26 Series1 Relative R-Value Under Field Conditions Start date: 6/5/96 West Wall - Specimen w5 120% 110% Average relative R-value 100% Average relative R-value over the heating season = 79% over the heating season = 82% 90% ) %

( 80% e u l 70% a V - 60% R

e 2-D Analysis v 50% i t 3-D Analysis a l

e 40% R 30% 20% 10% 0% 120 150 180 210 240 270 300 330 360 Oct 3, '96 Jan 1, '97 Apr 1 May 31 Time (Days)

27 Relative R-Value Under Field Conditions Start date: 6/5/96 West Wall - Specimen w5 120% Average relative R-value 110% over the heating season = 88% Average relative R-value 100% over the heating season = 88% 90% ) %

( 80% e u l 70% a V - 60% R

e 40% R 30% 20% 10% 0% 510 540 570 600 630 660 690 720 Feb 15, '98 Oct 18 Dec 17 Time (Days) Apr 16 May 16

28 Relative R-Value Under Field Conditions Start date: 6/5/96 West Wall - Specimen w6 120% 110% 3-D Analysis Average relative R-value 100% over the heating season = 70% 90% ) %

( 80% e u l 70% a V - 60% R e v 50% i t 2-D Analysis a l Average relative R-value

e 40% 79% R over the heating season = 30% 20% 10% 0% 120 150 180 210 240 270 300 330 360 Jan 1, '97 Oct 3, '96 Time (Days) Apr 1 May 31

29 Relative R-Value Under Field Conditions Start date: 6/5/96 West Wall - Specimen w6 120% Average relative R-value 110% over the heating season = 76% Average relative R-value over 100% the heating season = 83% 90% ) %

( 80% e u l 70% a V - 60% R

e 40% R 30% 20% 10% 0% 510 540 570 600 630 660 690 720 Jan 26, '98 Sep 28 Nov 27 Time (Days) Mar 27 May 26