LEED v4.1 BD+C | MR credit Building Life-Cycle Impact Reduction (Option 2)

Data & Construction Materials
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1

Hello everyone,

I am performing a Whole-Building Life-Cycle Assessment for a hotel building in Portugal according to the LEED v4.1 BD+C MR credit Building Life-cycle Impact Reduction (Option 2) requirements.

The following construction product is available in the project’s design stage bill of quantities:

a) Product name: hollow clay brick for use in non-bearing protected masonry, with passive exposure and acoustic, thermal, and fire resistance requirements;
b) Manufacturer: PRECERAM (300x200x90mm, 705 kg/m3) [1];
c) Quantity: 367.17;
d) Available unit: m2.

The following construction product is available in the One Click LCA library:

a) Product name: terracotta brick with hollow chambers for facade application, 30 mm thickness, 237.5-500 mm height, up to 1500 mm length, 42 kg/m2, 2200 kg/m3 (One Click LCA);
b) Available units: m2, kg, ton, m3.

Since the only similar construction product in the One Click LCA library has different technical characteristics (e.g., dimension, density), should I still proceed with the element mapping despite the possible distortion of the emission results? What is the recommended approach in this situation?

Thanks in advance for your insights.

[1] https://preceram.pt/documentos/DOP_Preceram_302009_170610.pdf (PT version).

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Hi João!

When looking for appropriate matches, commonly, the exact material might not have an EPD (e.g. in this case the manufacturer has no EPDs). The rule of thumb is to find the closest matching product even when it’s not a perfect match.

From your description, your product would be non-bearing which means a brick meant for facade application could work. A terracotta product is suitable for clay bricks, however, I would also try searching e.g. ‘clay’ when on the materials page as there are hundreds of clay products in the database.

As you have a density for your product (705 kg/m3) you could try to find a similar product, otherwise, you may end up with more materials than in your project. You could also scale a resource to match the specifications, e.g. reporting it in kilograms as we can calculate the weight of your specified product based on its density. If you manage to find a similar product, which we know has a similar manufacturing process and weighs about the same, it will be quite close to what the emissions would be in reality.

Let me know if you have any further questions!

1 Like
3

Hello,

I’m mapping an air-cooled chiller from BlueBox (Omicron SKY S4 R5 HE 29.4)[1] with the following technical characteristics:

a) Heating capacity: 269 kW;
b) Refrigeration capacity: 250 kW.

[1] Datasheet - https://www.swegon.com/siteassets/_product-documents/chillers-and-heat-pumps/product-sheet/_multi/omicron-sky-s4-r5.pdf

In the One Click LCA’s database, I found similar equipment from Carrier SCS (AquaForceTM Vision 30KAV 800)[2] with the following technical characteristics:

a) Refrigeration capacity: 791 kW
b) Weight: 5.811,5 kg.

And the following environmental profile:

c) Functional unit: producing 1 kW of cooling, based on the appropriate usage scenario defined in standard EN 14825 and throughout the product’s reference service life (RSL);
d) GWP (A1-A3): 73,6 kgCO2eq/kW (58,2 kgCO2eq/unit).

[2] EPD - https://eto.carrier.com/litterature/EE/10519_PEP_03_2019_30KAV.pdf

This EPD [2] presents the environmental impacts:
a) Corresponding to the functional unit (1 kW - refrigeration capacity)
OR
b) Corresponding to the declared product - actual product (1 unit).

The problem is that since I want to scale the second equipment (Carrier SCS)[2] to match the refrigeration capacity of the first (BlueBox)[1]:

a) The unit option for the second equipment (Carrier SCS) in the building material input section should be the same as expressed in the EPD (kW);
b) Instead, all three options available correspond to energy units (kWh, MJ, or MWh).

While checking for a possible error within the software (kWh instead of kW) by introducing 791 kW in the quantity field, the following results were obtained:

a) For materiais (A1 – A3): 58 ton (as per EPD);
b) For transport (A4): 136 ton (calculated considering a total mass of 791 kWh x 5.811,5 kg/kWh = 4,6 ton!!).

I believe this is a mistake, but I would request your clarification.

Thanks in advance for your insights.

4

Hi João,

Thanks for your thorough explanation, that’s very helpful. Your calculation based on kWh indeed leads to such emissions for transportation, however, this is due to how such resources are included in the database. Often the manufacturer does not provide a weight per kWh, just per unit, which means we may have to make a slight change to how the weight per kWh would be calculated.

  • Would you be able to provide me with the exact name of the resource in question, so that I can create a ticket for our data specialists? Carrier CSC has a large number of resources in the database, this would speed the request up significantly.

In the meantime, I can suggest another workflow that may lead to a good estimation of emissions for your product. When applying scaling there are generally three different ways we can go.

  1. Taking a similar resource
  2. Scaling based on capacity (in this case either heating or refrigeration)
  3. Scaling based on weight

If the products (from BlueBox and Carrier SCS) are similar in design, their material makeups may be similar too. The Omicron SKY 29.4 has an operating weight of 3600 KG, which means you could scale the AquaForce by quantity of weight instead.

3600/5811,5 = 0.61

If you would include 0.61 as the quantity, it could be a reasonable estimation emission-wise, and you would not have the issue with the transport emissions being calculated.

Looking forward to hearing back from you.

1 Like
5

Hello,

The name of the resource in question is “Liquid chiller for air conditioning applications, per kW, 5811.5 kg/unit, 30KAV 800 (Carrier SCS)”.

Thanks again for your assistance.

6

Thanks for getting back to me, I have created a ticket for our data specialists. They will adjust the mass of the product for the resource reported per kWh to ensure the transportation mass is not overreported.

I’ll let you know when this change has been made.

1 Like
7

Hello,

Shouldn’t the product mass be adjusted per kW of refrigeration capacity rather than per kWh, as stated in the EPD?

I look forward to your response.

8

Hi João, thank you for your reply. We will adhere to EPD rules, as the functional unit to report this product is set to ‘kWh, MJ and MWh’, the calculation will need to match these types. This process is more common with MEP equipment. Once this resource has been adjusted you can see how the calculation lines up with more representative transportation emissions.