Physically Accurate MEP Engineering Software

Complete HVAC, Plumbing, and Controls calculations validated against ASHRAE 140, DOE Reference Buildings, ACCA Manual J 8, and IEEE 1584-2018. Title 24, ASHRAE 90.1, and IECC compliance-check engines built-in.

Start 14-Day Free Trial See Features
1,300+ Engineering Modules
14,000+ Validation Tests Pass
523 Weather Locations
JΔS Engineering Suite - Professional MEP Design Software

Everything You Need for MEP Design

From load calculations to compliance reports, all in one powerful suite.

HVAC Load Calculations

Accurate heating and cooling load calculations using ASHRAE methodologies. Room-by-room analysis with detailed breakdowns.

Energy Compliance

Implements Title 24-2025, ASHRAE 90.1-2022, and IECC 2024 prescriptive + performance paths. Generates NRCC, LMCC, and NRCI forms automatically. Final compliance determination is made by the AHJ.

Plumbing Design

IPC, CPC, and UPC code support. Fixture unit calculations, pipe sizing, and water demand analysis.

Revit Integration

Seamless Revit integration with 3 specialized add-ins. Import room data, run clash detection, and boost MEP productivity.

Equipment Selection

Chillers, boilers, pumps, fans, VAV boxes, and more. Manufacturer catalog integration with performance curves.

Energy Simulation

8760-hour annual energy simulation. TMY3/EPW weather data support. DOE-2 compatible outputs.

See It in Action

A professional desktop application built for real MEP engineering workflows.

JΔS Engineering Suite - Project Dashboard with sidebar, workflow bar, and room load summary

Project Dashboard

Navigate 1,300+ engineering modules through an organized sidebar. Track project progress with the 7-step workflow bar from Project Setup to Final Reports.

HVAC load calculations with room data, wall exposures, and cooling load breakdown

HVAC Load Calculations

Room-by-room heating and cooling load analysis using ASHRAE methodologies. Wall orientation breakdown, CLTD/CLF factors, and detailed component-level results.

Title 24 and ASHRAE 90.1 compliance checking with NRCC forms and Appendix G results

Energy Compliance

Automatic NRCC/LMCC form generation for Title 24. ASHRAE 90.1 Appendix G with 4-rotation baseline, ECB calculations, and unmet hours tracking.

Energy Hub - tabbed interface for 8760-hour simulation, parametric sweeps, and Appendix G analysis

Energy Hub

One-stop interface for whole-building energy analysis. 8760-hour annual simulation, ASHRAE 90.1 Appendix G four-rotation baseline, parametric sweeps, and unmet-hours tracking.

Equipment Schedule - tagged equipment list with manufacturer model selection and AHRI corrections

Equipment Schedules

Auto-tagged equipment lists with manufacturer model selection (Greenheck, Trane, Carrier). AHRI 340/360 and 550/590 correction factors applied at design conditions.

Reports module - PDF, Excel, and CSV export with engineering deliverables

Reports & Deliverables

Professional PDF, Excel, and CSV output. Stamped engineering deliverables, NRCC/LMCC forms, and a complete project report bundle ready for client review.

What's New — May 2026

Recent investments in physical accuracy, validated against the strictest published references in the industry.

Revit Clash Detection — BirdTools-Class

BVH broad phase + parallel narrow phase. In-Revit ElementIntersectsSolidFilter, persistent symbol blacklist, BB-volume reject, real-time monitor with 5-sec debounce, freeze prevention, 3D/2D view nav, free-text result search, view colorization. 50K×50K elements in under 2 minutes.

ASHRAE 140 Path B IRT Solver

6-patch interior radiation transfer matrix solver with linearized Stefan-Boltzmann coupling and surface-to-surface view factors. Independent thermal engine validated against the ASHRAE Standard 140 envelope test suite.

CBECC Wrap for Title 24 Nonres

Path A: full CBECC-Com wrapper for California Title 24 nonresidential compliance submissions. 313 round-trip tests pass against real CBECC 2025.2.1 install. Generates valid .cibd25 XML for CEC submission.

IEEE 1584-2018 Arc Flash

Full Annex D coefficient transcription — electrode configuration (VCB/VCBB/HCB/HOA), gap, enclosure size correction. All 21 worked examples pass within ±0.0%. NFPA 70E PPE category labels generated from the 2018 model, not legacy 2002.

ACCA Manual J 8th Edition

Complete table support — Tables 1B, 3A, 3D, 4, 4A, 4D, 5A, 5B, 5C, 5D, 7E. Section 9 calibration applied. Residential load calculations validated against ACCA's own published worked examples.

DOE CRB Cross-Validation

Continuous validation against the DOE Commercial Reference Buildings (16 prototypes × 16 climate zones). Energy use intensity targets within ±5% of DOE/PNNL published values where the engine matches their multi-zone topology.

Built for MEP Engineers

A comprehensive engineering platform designed for real-world MEP workflows.

Download JΔS Engineering Suite

Available for Windows 10/11. Requires 8GB RAM, 2GB disk space.

JΔS Engineering Suite v1.3.2

Latest release - May 2026

  • Windows 10/11 (64-bit)
  • Size: ~500 MB
  • Includes 3 Revit add-ins
Sign In to Download

Note: Windows may show a SmartScreen warning for new software. Click "More info" then "Run anyway" to install. The software is safe.

Also Available — Free Standalone Tools

No license, no registration. Download instant calculators for daily reference: PsychChart Pro (psychrometric calculator), DuctSizer Pro (round/rectangular/oval duct sizing), PlumbingCalc Pro (IPC/UPC/CPC fixture calculator), and Viewer3D Pro BETA (standalone 3D BIM viewer with PBR rendering).

Explore Free Tools

Get in Touch

Have questions? We're here to help.

Email Support

james@jsengineeringsolutions.com

Response Time

We typically respond within 24 hours

Documentation

View our documentation