Apex Heat App updates in 2026

Air-to-air heat pumps are now calculated as an investment option

For a building without a heat pump, air-to-air heat pumps can be calculated with a chosen model and number of units, alone or with an exhaust air heat pump. They heat beside the existing system, which still makes the hot water and the rest of the space heat, and in the energy subsidy they take the 40% heat pump row. The options are off by default, so saved projects' results do not change until they are switched on.

Borehole fields are sized with the brine temperature model instead of a yield-per-metre table

A field's yield per metre is calculated with the brine temperature model from the field's number of holes and depth, unless you enter the yield yourself. Calibrated to the simulated wells of Helsinki's energy well report, the model keeps the mean fluid temperature at −1.5 °C or above in the coldest month and at −5 °C or above through a three-day peak over 30 years, which gives one hole in Helsinki's climate 111 kWh/m at 150 metres, 121 kWh/m at 300 metres and 136 kWh/m at 500 metres. The same model calculates the brine temperature month by month from the area's climate instead of a fixed 3 °C, so the ground source sCOP changes.

Boreholes can be placed on the street and park land beside the lot

Two new options add land beside the lot to the drillable area, with the city's permission: either the street halfway to the opposite lot plus a narrow strip of the adjacent park, or the whole adjacent park near the lot. With the first, drill starts stay on the lot and the holes are drilled at an angle, and a large lot that already fits enough boreholes gets no street or park land added.

A heat pump model can be chosen from a list of manufacturers' real models

A sizing-table row can take a ground-source or air-to-water model, and a number of units of it, from a catalogue fitted to manufacturers' published data: 145 ground-source and 67 air-to-water pumps. The calculation uses the chosen model's COP, operating limit and cold-weather output, so the row's sCOP and coverage are the model's. When the building's existing heat pump is chosen from the catalogue, today's heating and the baseline for savings run on that model.

• Improved: The solar array's size can be entered in kilowatt-peak
• Improved: The energy subsidy can be calculated for investments you choose
• Calculation change: The boreholes' distance from a neighbour's plot grows with their depth
• Calculation change: Window and door renewals default to U-value 0.70 W/(m²K), so they count towards the energy subsidy
• Calculation change: Heat pump COP curves were fitted to manufacturers' measurements
• Calculation change: Current electricity cost rises where a building has a heat recovery machine

Results are now also shown building by building

A building switcher shows each building's own figures, and heat recovery calculated per ventilation unit is shown unit by unit. Heating systems, heat recovery, solar and envelope measures can be calculated for the whole property or building by building, and the guidance says when the per-building choice makes sense.

Shared workspaces are available to every user

In a shared workspace colleagues see and edit the same projects, while a personal workspace's projects are seen only by the person who made them. Anyone can create a new shared workspace from the menu, invite colleagues to it and switch between workspaces.

Installation work is priced dearer in the capital region

Municipalities fall into the six areas of Haahtela's tender price index, and the installation and site work factor ranges from 0.92 to 1.08 by area. In Helsinki, Espoo, Vantaa and Kauniainen the factor rose from 1.0 to 1.08, and in Turku from 0.975 to 1.00. Oulu belonged to no group before and took the cheapest factor, 0.95; its factor is now 0.96.

The results show the property's energy flow as a diagram

The diagram runs from current consumption to consumption after the recommended investments: space heating demand, circulation losses, free energy, heat pump electricity, energy efficiency savings and the solar share. Its left side is the current state, and only the two right-hand sums describe the state after the investments; with no investments, the diagram shows the current state alone.

The consumption year normalises heat consumption for weather

When the consumption year is given, the space heating share is corrected by the ratio of heating degree days between the measured year and the calculation's reference weather while hot water stays as it is, so consumption measured in a mild year no longer understates a typical year's heat demand. Stored hourly series are normalised from their own year, and the factor shows in the results and the report. Without a year the results do not change, and a heat pump property's consumption is not normalised.

• Improved: Design costs can be added to the energy subsidy, by default 3% of the recommended investment
• Improved: A system is chosen and costed in one section
• Improved: The IFC and energy performance certificate uploads are no longer in beta
• Improved: Energy reports for renovation projects can be made
• Calculation change: An air-to-water heat pump's electric backup boiler is sized only for the peak the pump leaves
• Calculation change: Oil and gas heated properties are recommended a pure heat pump over a fuel hybrid
• Fixed: A price entered for a building's heat distribution upgrade is used in every heating solution
• Fixed: An investment price entered with VAT is no longer taxed twice

Heat pump capacity fell, now that it is sized for a target share of the year's heat energy

The capacity is now the smallest that covers 98% of the year's heat energy for ground source and 95% for air-to-water and air-to-air; it used to be a fixed 70% of peak power. In the calculation's default example the ground source capacity fell from 143 kW to 120 kW, and to 73 kW with heat recovery, where the sizing covers the remaining demand. In close cases the recommendation can change. Detached houses are still sized for full peak power, and a coverage share of your own can still be entered.

Apex Heat can be used from an AI assistant through the MCP connector

Claude, ChatGPT or another assistant that supports MCP can open Pro projects, read calculation results, import consumption, energy performance certificate and IFC files, and make reports. Every change that saves is confirmed first. The connector is in beta and is switched on account by account, and apexheat.io/connect shows how to add it.

Reports are made as editable Word documents

Every report can be downloaded as a Word file, which suits editing the report yourself. The PDF still comes straight from the app for sharing with the customer, with the same content and the report theme's fonts.

The certificate also comes as a target-state version after the investments

A second certificate shows the building on the same ARA form after the chosen measures: heating system, energy efficiency measures, solar power and measurements. Without a choice, the recommended package is used. The choices apply to this certificate only and change neither the saved data nor the calculation's recommendations.

A draft energy performance certificate can be previewed before sending it to ARA

The draft is ARA's 2018 form on eight pages, built from the same data that is sent to the register. Every page is marked as a draft, and nothing reaches ARA until it is sent separately. The English version is an unofficial translation.

Building details can be imported into the form from an IFC model

The model is analysed, its buildings are matched to the project's buildings, and the floor areas, wall and window areas per direction, volume, number of floors, U-values and construction year are reviewed before they are written into the form. The upload is now available to everyone as a beta in the project's Upload files section.

• Improved: District heating energy price, demand charges and emission factor can be entered
• Improved: A property buying district heat through a neighbour can calculate its own connection
• Improved: Consumption files can also be imported at monthly resolution
• Calculation change: Walls shared by adjacent buildings are deducted from the exterior wall area
• Calculation change: Switching to district heating now includes the cost of waterborne heat distribution
• Calculation change: A solar plant is recommended by net present value
• Fixed: A field that blocks the calculation can be reset to its estimate with one click
• Fixed: Address search no longer picks a building from the wrong municipality by mistake

The report's savings potential now counts every measure

The savings potential summed only profitable measures, so where nothing pays for itself it read €0 a year beside the chart. The sum now covers every measure and says why nothing is recommended. Ground source solutions that cannot be built on the site drop out of the list of alternatives, and the report names the reason.

The app and the report tell on what basis a heat pump was recommended

The recommendation is chosen among the calculated heat pump solutions, primarily by net present value, and a note under the results table says which rule decided it: highest net present value, the only option, full ground source over a hybrid, suitability for an apartment building, or better efficiency. If connecting to district heating would give a higher net present value, the app and the report say so and advise checking the connection's availability and price.

• Improved: A shared workspace's project list can be filtered by person
• Improved: Personal projects can be moved into a shared workspace
• Fixed: The report's energy efficiency recommendations show as text, not as raw label codes
• Fixed: Solar power is calculated for a heat pump building even when no heat pumps are compared

Building details can be imported into the form from an energy performance certificate PDF

Building and property values are read from one or more certificates and reviewed before they are written into the form, and property totals are split between buildings by heated floor area. Only machine-readable PDFs can be read, not scanned ones. The feature was released as a beta.

Energy performance certificates and energy reports for new buildings

A building permit stage certificate gets the E-number limit, the design heating power and the summer indoor temperature, and the energy report downloads as a PDF. The calculation uses standardised use, so real SCOP, measured air leakage and actual purchased energy do not affect the result. A building drawn on the map is treated as new construction by default.

The certificate counts more cooling electricity for chillers and less for ground source free cooling

The air-cooled chiller's SPF default fell from 3.2 to 2.5 and the water-cooled one's from 4.0 to 3.0, per table 9.2 of the ministry's guide. Ground source active cooling (3.2 to 3.0) and free cooling (10 to 30) are read from the table's nearest rows. The equipment's real seasonal performance is a field of its own, apart from the certificate's SPF.

The calculation estimates a residential building's 2026–2027 energy subsidy

The estimate tells whether the recommended package of measures meets the subsidy's E-number condition, and the amount: at most €4,000 per apartment and at most 50% of eligible costs. The decree was still a draft, so the result is preliminary, and it compares against the current E-number rather than the level at the time of construction. The estimate downloads as a one-page PDF.

A building missing from the register can be added on the map

The building's location is picked on the map and its mandatory details filled in, after which it is calculated like a registered building. The project can be created only once every manually added building has its mandatory fields filled.

• Improved: The form has a field for gross floor area
• Improved: The boreholes' distance from the building and from the lot boundary can be set
• Improved: The building ID of a certificate sent to ARA can be edited
• Improved: Address search completes the address as you type
• Improved: A building's shape can be drawn and edited on the map
• Calculation change: The certificate's 4,200 kWh hot water cap applies to each apartment in terraced and linked houses
• Fixed: An entered building volume is used for the district heating demand charge
• Fixed: A recommended hybrid or district heating blend no longer lacks an E-number

A building without a registry building ID is marked for checking

The building ID is shown only when it comes from the Ryhti building register; otherwise the label reads "no building ID". Such a building's form asks to check the building type, floor area, heating, construction year and ventilation, because the defaults rest on coarser open data.

All applicable investments are calculated by default

The technologies to calculate are switched on by default, and the calculation leaves out solutions that do not apply to the building.

The certificate no longer counts auxiliary electricity for heat pumps, which lowers heat pump buildings' E-numbers

Air-to-water, ground source and exhaust air heat pumps carried 0.5–1.5 kWh/m² of auxiliary electricity, and now carry none, because a heat pump's SPF already covers its own pumps and fans; actual auxiliary electricity can still be entered. The hot water circulation pump's 0.1 kWh/m² now applies only to buildings with a circulation line, so the others' E-number falls slightly. In the calculation's sample cases the E-number fell by a few units.

Energy performance certificates are available on every account

Certificates used to be enabled account by account, and now they are on by default for every account, accounts in their trial period included. They can still be switched off for an account whose contract does not cover them.

A project can show only the investment calculations or only the energy performance certificate

The choice hides the other task's fields and results, but the calculation always runs in full. The choice appears on accounts with energy performance certificates enabled.

The certificate's suggested measures can be prefilled from the investment calculations

With one click, recommendations and observations are written in Finnish and Swedish from the calculated investments: costs, savings, payback and the change in E-number. Primary and alternative measures get paragraphs of their own. The text can be edited, and the app asks for confirmation before replacing existing text.

• Improved: An energy performance certificate can be made for part of a building
• Improved: The certificate's actual purchased energy can be entered from meter readings
• Improved: The summary panel shows the recommendations for the whole property
• Improved: Replacing windows and replacing doors have their own costs and installation years
• Improved: Window transmission and shading factors can be given per compass direction
• Improved: The E-class reference values can come from the official certificate or be recalculated
• Fixed: The certificate counts an existing exhaust air heat pump
• Fixed: Quickly entered values are no longer lost while saving

The power, production and orientation of the current and the planned solar plant can be entered

For both plants, the power in kilowatts peak, annual production, tilt, azimuth and panel efficiency can be given. If production is not given, it is estimated from the power, orientation, tilt, efficiency and local irradiation. The current plant's production fills in the certificate's solar electricity.

A nearly profitable investment is no longer rejected outright

When the net present value is negative but the payback time is under 20 years or the shortfall is under 10% of the investment, the PDF report softens the recommendation's wording and the Pro app shows a warning under the results table.

A building can be given a secondary heating system

The secondary heating gets a heating type, a heat distribution and the share of heat energy it covers, and the certificate's efficiencies, SCOP and auxiliary electricity can be given for both heating types. The certificate results, energy prices and emissions are weighted by the shares.

The effect of an air tightness measurement on the E-number can be calculated as an investment

After a measurement, the energy performance certificate can use the building's real n50 air leakage rate instead of the default, which lowers the E-number. The measurement itself does not change energy consumption. The cost depends on building type and size, and in buildings other than detached houses the measurement is included in the calculation by default.

The results tell whether a building meets the EU taxonomy criteria

Eligibility is assessed for the current state and for each solution: whether the building is in the best 15% or 30% of the national building stock, and whether a renovation reaches a reduction of at least 30%. The thresholds depend on building type, and the result shows in the E-class table and the PDF report.

• Improved: The certificate counts the heat from an air-to-air heat pump and a fireplace
• Improved: The year used in the calculation can be chosen from uploaded consumption data
• Improved: Actual purchased energy consumption is carried into the energy performance certificate
• Improved: Uploaded consumption data replaces and locks the consumption fields
• Improved: The energy performance certificate and the E-number calculation are no longer in beta
• Improved: Fuel heating consumption can be entered in the fuel's own unit, such as litres of oil
• Calculation change: In the certificate, a detached house's hot water net energy is capped at 4,200 kWh a year
• Fixed: An entered electricity connection size is used for the cost of enlarging the connection

A building can have several ventilation units, each with its own details

Each unit gets a system type, heat recovery and airflows. The building totals are calculated from the units: heat recovery efficiency as a weighted average and the airflows as a sum.

Measured consumption can be imported from a file as the basis of the calculation

A heat or electricity consumption series can be uploaded from a CSV or XLSX file, and it is saved to the project and used in all results. The series can target one building or the whole property, in which case it is split between buildings by floor area.

The E-class is now calculated with the energy performance certificate calculation

The current E-number and each solution's E-number are calculated with the same calculation as the energy performance certificate. Heat pump options use the calculation's real seasonal coefficients of performance instead of the certificate defaults, so E-numbers can differ from before.

The building envelope is entered in the main form

The main form gained the U-values of walls, base floor, roof, windows and doors, the number of floors, the air leakage rate and thermal bridges. Wall and window areas and window U-values can be given per compass direction, and the form warns when an entered total area overrides the per-direction areas.

Projects are saved, and you return to them from the project list or the address search

Form changes are saved and loaded automatically. Saved projects appear in the project list with their address and last edit date, and the same project opens from the list or by searching its address.

• Improved: A heat pump building's input can be the heat pump's electricity consumption
• Improved: The results table shows electricity consumption alongside heating
• Improved: Target U-values can be given for energy efficiency measures
• Improved: Hybrids and district heating combinations get their own E-number
• Improved: The map shows the lot boundaries
• Calculation change: A detached house's solar plant is always sized for total electricity
• Fixed: A district heating network with no emission data gets the national average instead of stopping
• Fixed: An outdated browser tab no longer overwrites newer data

Energy efficiency measures and heat pump combinations now improve an electrically heated building's E-class

In buildings heated by electricity, ground source or air-to-water heat pumps, energy efficiency measures did not improve the E-class, and a heat pump combined with measures gave class G. The calculation now separates heating electricity from other electricity, so the result no longer depends on which heating the input named. E-numbers of district heated and oil heated buildings did not change.

Energy costs have a section of their own, where the prices can be changed

The section shows the prices of electricity energy, distribution and tax, and of heating. The app picks the cheapest local prices and the most suitable distribution tariff, but the tariff and the prices can be changed.

Projects with several buildings are calculated building by building, each with its own details

Each building's details can be edited separately, and heat consumption is calculated per building and summed.

District heating and its combinations became options to calculate

A switch from the current heating to district heating can be calculated, also with an exhaust air heat pump or with an electric boiler that optimises costs. Replacing the district heating heat exchanger and modernising heat recovery can also be calculated.

A heat pump can be calculated alongside the current heating

New solutions to calculate are a ground source or air-to-water heat pump alongside the current heating, also with heat recovery, and a combination of ground source and air-to-water heat. The technologies to calculate are now chosen in groups: ground source, air-to-water, heat recovery, cooling, waste heat, solar power and district heating.

• Improved: The consumption form separates space heating, hot water and resident electricity
• Improved: Calculating a three-building property got faster, from 5.1 to 2.6 seconds
• Improved: Investment and maintenance costs can be edited for every solution
• Improved: The discount rate and the annual growth of heating and electricity costs can be set
• Improved: A calculation can run without heat pumps, for example for solar alone
• Calculation change: Energy efficiency measures are also calculated for buildings with a heat pump
• Calculation change: A building with a heat pump is only offered a better heat pump
• Calculation change: Ground source alone is recommended over a combination when the difference in return is small

The default solar plant price fell, most for small plants

The price per kilowatt-peak fell by €200 before VAT and the regional factor for plants under about 18.5 kWp. For larger plants the cut shrinks, because the floor of €850 per kilowatt-peak stayed as it was, and from about 98 kWp up the price did not change.

Solar plants on residential buildings are sized for property electricity

In apartment buildings, terraced houses and detached houses, the solar plant is now sized for property electricity, meaning ventilation, heat pumps and common areas, not for total electricity consumption. In apartment buildings and terraced houses the sizing can be switched to total electricity, which requires setting up an energy community with the residents. Other buildings are still sized for total electricity.

The energy performance certificate form asks for the details of the heating and hot water systems

The form gained, among others, supply air reheating, hot water tank and circulation losses, heating devices on the circulation line such as towel dryers, and distribution pipes running through unheated space. With electric floor heating in wet rooms, 35% of the net space heating demand is allocated to electric heating and 65% to the main heating system.

• Improved: Solar panels can be sized for the recommended heat pump's electricity use
• Improved: A building is selected for the calculation by clicking its outline on the map
• Fixed: Drilling on a small detached house lot is no longer wrongly marked impossible
• Fixed: A ground source heated building's current heating no longer shows as district heating
• Fixed: An entered borehole yield per metre is used in every calculation