HVAC Design & Mechanical Drawings — Midland
Midland publishes no mechanical checklist, which means the requirement usually arrives after you have applied. Here is what they will want, and the design temperature your calculation has to use.
A Midland permit package starts from the SB-1 design temperature of -24 °C (Table 2). It includes the CSA F280-12 heat loss and heat gain, ventilation design data for OBC 9.32, duct design and layout, and the Energy Efficiency Design Summary, reviewed and sealed by a BCIN-registered designer. Heat loss and gain from $395; the full mechanical package $695; 48 hours from complete plans.
Midland does not publish a mechanical checklist
We looked. Midland's building department publishes no list of the mechanical documents it wants with a new dwelling application — applications go through their permit portal and the requirements come back case by case.
That is worth knowing before you apply, because it means the requirement arrives after you have submitted rather than before. The practical answer is to phone the building department and ask what they want in the mechanical package for your specific project, then get it done before the file is opened rather than after.
What they will almost certainly want, because the Code requires the equipment to be sized from it: a heat loss and heat gain calculation, a ventilation design, and an Energy Efficiency Design Summary.
The design temperature
Every number in a heat loss calculation depends on the outdoor temperature the house is designed for, and the province sets it — not the designer.
Midland: -24 °C (-11 °F) — January 2.5% design temperature January 1%: -26 °C · Degree-days below 18 °C: 4,200
Source: Ontario Building Code SB-1 (2024), Table 2 — Climatic Design Data. Basis: listed in SB-1.
A calculation run at the wrong design temperature is wrong by roughly the amount the temperature is wrong by, and it is one of the commonest reasons a reviewer sends a package back. If you are comparing quotes, ask which design temperature the designer is using before you compare anything else.
What each document actually is
| Document | What it is |
|---|---|
| Heat loss and heat gain calculations | The room-by-room load. Everything else is sized off this. |
| Formula sheet | The working behind the numbers, so a reviewer can follow them. |
| Thermal load calculator | The envelope assemblies and areas the loads were built from. |
| Air leakage calculator | The infiltration assumption, stated rather than buried. |
| Residential ventilation summary | The OBC 9.32 ventilation design, on the HRAI summary form. |
| Duct design and layout | Supply and return sizing, register locations, cfm per room. |
| Energy Efficiency Design Summary | How the house meets SB-12, prescriptive or performance. |
| Radiant in-floor design | Loop layout, spacing, manifolds and lengths. |
| Hydraulic load calculations | Flow and head for a hydronic system. |
Who is allowed to sign it
You hire a qualified designer. They complete the Schedule 1 Designer Information Form with their BCIN and take responsibility for the design.
You are the owner, building on your own lot. Ontario Building Code Division C, Article 3.2.5.1.(3)(b)(i) exempts an owner who designs a house they own from the designer qualification requirements. You can file the documents yourself. The calculations still have to be correct — the exemption is about who may design, not about the standard the work has to meet.
Tell us which applies and we will tell you what you need before you pay.
What it costs
| Includes | Price | Turnaround | |
|---|---|---|---|
| Heat loss and heat gain | Room-by-room loads, worksheet, design conditions, equipment sizing basis, assumptions, seal page | $395 | 48 hours |
| Full mechanical package | The above plus ventilation design, duct design and layout, EEDS, and radiant layout where applicable | $695 | 48 hours |
Forty-eight hours from complete plans and payment. If the building department asks for a correction to something we got wrong, we fix it and reissue at no charge while your application is open.
See a complete sample package →
Common questions
Do I need all of these documents? Not always. A heat loss calculation alone satisfies some permits; a new dwelling with a hydronic system needs close to the full list. Send the plans and we will tell you which.
The department has already asked and my build is held up. That is the most common reason people call. The 48-hour turnaround exists for exactly that.
My HVAC contractor says he will size it. He may be right about the equipment. The building department still needs the documents, and the Code requires equipment capacity to be based on the calculated design heat loss.
I'm adding a basement apartment, not building a house. Different job: no drawings, an existing furnace, and a check that it can carry both units. Here is how that works → The design temperature and the checklist above apply to it just the same.
Does an ICF or high-performance house change the answer? Same procedure, different inputs. The result usually comes out substantially lower, and more of the difference comes from air sealing than from the wall's R-value. We run that comparison on every job.
Start
Send your plans — we'll tell you what you need before you pay →
Building in Midland? Full HVAC package in days.
Upload your plans and we produce the complete BCIN-stamped mechanical design at the correct -24°C Zone 6 design temperature, ready for the Town of Midland Building Department.
See the PackageGet a Free QuoteBuilding in Midland: what changes the design
Midland is on the southern tip of Georgian Bay, and it is a lot colder on paper than most people expect: about the same as Barrie. A design that uses a Toronto temperature here will undersize the equipment.
Midland has an older town core, newer subdivisions on the edges, and plenty of waterfront homes and cottages toward Tiny and Tay. Many of those cottages are being turned into full-time homes, which means real insulation, a permanent heat source and mechanical ventilation, all on the permit drawings.
Outside the gas lines, propane, heat pumps and wood stoves are common. We design around the fuel you actually have, and we show any backup heat on the drawings so the examiner can follow it.
Common Midland projects we design for
- Cottage to year-round conversions
- Older homes in the town core
- Propane and heat pump systems outside the gas lines
- Additions and second units
What to send us
- Floor plans and elevations, or a clear sketch with room sizes
- Window sizes and type (or the window schedule)
- Your fuel: natural gas, propane, oil, electric or heat pump
- Anything special: radiant floors, a garage or shop, a second unit
What the Midland examiner looks for
The building department wants a CSA F280 room-by-room heat loss at the Midland design temperature (-24 C), equipment sized from that number, a duct or piping layout, ventilation that meets the code, and the designer's BCIN on Schedule 1. Miss one and the permit comes back. We send it all together so it goes through the first time.
Have plans ready? Send them in and we will call you back with a price. Want the background first? Read what a full HVAC design package includes.
Upload your floor plans and we deliver a BCIN-stamped CSA F280 heat loss report from $395, or the complete HVAC permit package — mechanical drawings, MVDS, Schedule 1, BCIN stamp on every page — from $695. Delivered in 48 hours, accepted by every Ontario building department. Free quote within 24 hours, no obligation.
- CSA F280 at your municipality’s design temperature
- MVDS & Schedule 1 included
- BCIN stamp on every page
- 48-hour delivery, province-wide
- Free quote in 24 hours — or call 705-533-1633