Welcome to OspreyBP! Your destination for quality Building Performance and Drone Services.

Building Performance
Manual JDS, Manual NDS, REScheck™, Air Balance, and Duct Leakage

Services We Provide

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Manual JDS

Manual J, D and S are standards for the proper design and installation of HVAC equipment and ductwork to meet residential IECC (International Energy Conservation Code) and Mechanical code.

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Manual NDS

Manual N is commercial HVAC Load Calculation and is part of the HVAC System Design Process. It is used to calculate the heating and cooling loads for commercial buildings. Manual D is the industry standard for sizing HVAC return and supply duct & registers to distribute the correct amount of heating and cooling to each room. Manual S for HVAC equipment sizing to meet code requirements. The Manual NDS ultimately provides HVAC design for a comfortable environment for commercial spaces. Osprey BP provides Commercial HVAC Design Services nationwide.

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REScheck and Manual J are both used to measure the building envelope versus the climate zone, but REScheck measures the suitability of the building’s insulation envelope against local climate zone and gives a pass or fail score. Manual J measures the building envelope versus the climate zone and provides sensible heat gain latent heat gain, and total heat loss. REScheck™ ensures your system meets necessary regulations and codes for the town the home is located, reducing the risk of costly fines or penalties. Not all building departments require REScheck.

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Air Balance

An air balance measures the performance of an HVAC (Heating, Ventilation, Air Conditioning) system and adjusts to provide the occupants a comfortably conditioned space. It involves adjusting the dampers in the ductwork and fine-tuning the airflow at each diffuser and grille to ensure equal and balanced air flow.

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Duct Leakage

Leakage from ducts can account for up to 20% of the energy losses in a building. Duct leakage tests can determine the amount and location the leakage is occurring.​

Sectors We Serve


Manual J D S are used in the initial home design process to determine the heating and cooling load (Manual J) so that the proper design and sizing (Manual D) and right HVAC equipment can be considered in the home’s design.


When a home has been designed using the Manual JDS upfront, the builder is able to send a detailed design to the HVAC contractor during the bidding process. The home can be tested and balanced to those specifications removing any ambiguity during the build.


A well designed, tested, and balanced HVAC system is crucial in creating an energy efficient, comfortable, and healthy indoor environment for the homeowner.

HVAC Contractors

It is more time efficient for HVAC contractors to quote and install when the specifications in the Manual JDS are provided. Once installed, the HVAC can be tested and balanced to those specifications thus meeting code requirements and avoiding rework.

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Meet our HVAC Design Specialist

Since 2011, Osprey Building Performance has been providing home designers, builders, and building owners services to ensure their homes are efficient, effective, and healthy homes.
Our team has credentials in:

  • HVAC Journeyman
  • HVAC Systems Designer
  • IDABO Residential Air Balancer
  • BPI Building Analyst
  • Whether the home is large or small, single-family or multifamily dwellings we can advise, design, test, and balance for optimal HVAC performance.

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