A ProAir system can be installed in an existing house. When improving insulation levels or doing other improvement works would be a particularly good time to consider installation of an MVHR system. Some examples of poor ventilation practice can be seen here. If major renovations are being carried out the job is nearly the same as a new build. It is generally possible to get the required airtightness level and it is also likely that the insulation will be improved as part of this work. If only minor work is being done a ProAir system can be installed if access can be provided to all the ceilings in the house.
In many houses condensation increases after having the walls and loft insulated. Condensation will occur on a surface which is cold relative to the surrounding air. It can be avoided by extra heating and ventilating the house well. Solving condensation problems requires a three pronged approach (i) reducing cold surfaces by insulation (ii) heating the space and (iii) ventilating well. See more on Condensation. Sometimes air quality disimproves after insulating a house. This is due to gaps around windows, doors etc. having been closed in. The air tightness level of the house has been improved. The volume of air coming into the house has been reduced. Stale air is now more prevalent inside. A ventilation system will solve the problem.
If the house is single storey (bungalow) access to all the ceilings can be generally easily arranged. In a two storey serving the first floor is similar to the situation in a single storey. Access to the ground floor ceilings maybe difficult. It maybe possible to run ducts directly from the loft area through wardrobes, presses etc on the first floor through to the ground floor rooms. Boxing in of ducts on the first floor is another option. Some of the work done in a two storey retrofit can be seen here. If it is a dormer access to the ground floor rooms maybe possible from the side lofts, storage areas etc.
Providing a system to do the top storey of a house maybe an option where it is not possible to get down to the ground floor ceilings. This would improve the ventilation on the first floor. However just getting just one extract and one supply downstairs would increase ventilation and improve heat efficiency in the house as a whole.
The benefits of installing a ProAir system are primarily that fresh air will be supplied and stale air will be extracted on a 24/7 basis. The relative humidity will be reduced. This will reduce the possibility of condensation and subsequent mould. Heating costs will be lower. Overall the result is that the house will be healthier and cheaper to run from an energy point of view.
In October 2013 the Government introduced the Home Renovation Initiative (HRI) as part of the 2014 Budget. It provides tax relief for homeowners by way of a tax credit at 13.5% of qualifying expenditure on repair, renovation or improvement work carried out on a principal private residence. This scheme was scheduled to end in December 2015. In Budget 2017 it was announced that the HRI would be extended for a further 2 years, up to 31 December 2018. Installation of a heat recovery system is in this category of work. Qualifying expenditure is expenditure subject to the 13.5% VAT rate. The work must cost a minimum of €4,405 (exclusive of VAT). This amount will attract a credit of €595. (The maximum qualifying expenditure is €30,000). Jobs can be combined so that the minimum is reached. See here for more information.
ProAir is VAT registered and will cooperate with customers when making claims etc.