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SHORT METHODOLOGIES FOR IN-SITU ASSESSMENT OF THE

INTRINSIC THERMAL PERFORMANCE OF THE BUILDING ENVELOPERémi BOUCHIE, CSTB

Pierre BOISSON, Simon THEBAULT, CSTBFlorent ALZETTO, Saint Gobain Recherche

Adrien BRUN, CEA

PERFORMER project – Funded by the EC under the 7th Framework Programme - Grant Agreement #609154

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PERFORMER PROJECT

PERFORMER project – Funded by the EC under the 7th Framework Programme - Grant Agreement #609154

■Founded by the 7th Framework Program of the European Union (project cost 8,5 M€)

■Aims :■To develop a comprehensive energy performance assessment framework for buildings■To develop innovative methodologies■To develop innovative tools (ICT tools, software…)

■Major European companies and research centers implicated:

■Reducing to gap between expected and actual energy performance of buildings

■A part of the gap is determined by intrinsic performance of the building envelope (workmanship quality), a specific task of PERFORMER Project is dedicated to find methods to measure in situ the thermal performance of a constructed envelope.

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NEED FOR INNOVATIVE METHODS■ Methods with occupancy

■ Energy signature methods : ■ The “signature” include ventilation■ Occupant behaviour (i.e. windows opening)■ Solar gains ? Other energy uses (hot water) ?

■ Methods with no occupancy■ Most studied: the co-heating test = “optimised” energy signature method (no

occupancy, no ventilation, just heat consumption, method for solar gains…)■ Good accuracy but practical problems:

■Applicable in cold climate/season (not in summer)■Need about a month with no occupancy in the tested building

■ Need for innovative methods to reduce time duration for the test, development of “short” measurement methods (< 10 days max)

PERFORMER project – Funded by the EC under the 7th Framework Programme - Grant Agreement #609154

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ISABELE METHOD■ Optimisation protocol:

■ Temperature difference minimized by adjusting:■ Thermal loss through the envelope (insulation + air infiltration)■ Dynamic parameters (energy stored of the thermal mass)

■ The “best” thermal loss coefficient HLC (W/K) obtained when measured and calculated internal temperature are the closest possible

PERFORMER project – Funded by the EC under the 7th Framework Programme - Grant Agreement #609154

Heating power injected (controlled and measured)

External solicitations (measured)

Tint mes

Tint calc

≠ to minimize

Tested building

Thermal modeling (RT 2012)

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QUB METHOD

■Done during the night and without occupancy to avoid non measured additional power

The simplestbuilding model

P(t)

TEXT

R

CTIN

𝑃=𝐾0 (𝑇 𝐼𝑁−𝑇 𝐸𝑋𝑇 )+𝐶∆𝑇 𝐼𝑁

∆ 𝑡

Objective : Measure the whole building heat loss in one night

Loss by transmission

and infiltration

Internal mass

storage

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INCAS PLATFORM

■88 m2 two-story individual house

■Roller blind closed to avoid radiations

■Temperature and energy consumption monitoring

■Use of in-house heating and ventilation system■Electrical resistance on terminal part of the airflow network■Limited ventilation losses using heat recovery system on exhausted air

PERFORMER project - 7th Framework Programme - Grant Agreement #609154

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MAIN RESULTS■ ISABELE method:

■ QUB method:

■INCAS-IMA house very airtight, few thermal losses by air infiltration (≈ 1 W/K): global measured heat loss very closed to heat loss by thermal transmission alone

■ Few thermal losses by air infiltration (Hv,inf ≈ 1 W/K)

■ Global measured heat loss HLC very closed to heat loss by thermal transmission alone: HLC ≈ Htr

■ Htr has been calculated using existing standards: Htr = 104 W/K

■ BOTH METHODS GIVE SIMILAR RESULTS, CLOSED TO EXPECTED VALUE

PERFORMER project – Funded by the EC under the 7th Framework Programme - Grant Agreement #609154

Test method

Heat Loss Coefficien

t HLC [W/K]

ISABELE 112QUB 99

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DISCUSSIONS■Need for “reference” value…

■ ISABELE and QUB method are being tested and compared to co-heating test value■ Feedback on methods applicability during warmer season (now…)

■ Feedback from a real building test (on Saint Teilo’s School, during easter holidays)

■ Is it possible to “deal with” existing in-house heating systems ?■ Problem of a real building: counting heat consumption, complex envelope, big volume,

non tested zone, solar gains…

■Replicable on every buildings types ?

■Are you ready to leave your all building empty for several days (minimum) ? Sampling by small zones may be difficult…

■Can we imagine on ICT kit to run theses methods on real buildings ?■ A key point: heating system: easy to control ? Possible to over-heat the tested building ?

Easy to measure heat consumption alone ?...

PERFORMER project – Funded by the EC under the 7th Framework Programme - Grant Agreement #609154