QI live in a 1950s end-of-terrace house. During the autumn, I noticed a thin veil of smoke in my hallway, and upstairs when I went to check it out further. I also checked the attic and the smoke was quite noticeable. My next door neighbour tends to light fires at the weekend and I called into them to let them know what was happening. They put out the fire and then had their chimney cleaned and checked out. It turns out there is a crack in the lining of the chimney. I am not against sharing the cost of any repair work as I would also light a fire on occasion during the winter months, but I would like to know for certain whether the liability is with one or both parties for the repair work.

A Generally speaking, the chimney of a terraced house is a party structure and structural repairs affecting the entire stack are a shared cost. However, maintenance of same generally falls to both neighbours, down the centre line of the party wall, with you maintaining the render or pointing and the flashings on your half. Very often you will see a terraced roof recovered and the flashing/haunching replaced to the centre line of the party wall.

However, with the flue lining the chimney will have a minimum of two flues; one per household. You will each be responsible for cleaning and maintaining your own flue. If it turns out to be a major structural issue requiring rebuilding of the chimney stack, then it may be a joint issue and a shared responsibility to rebuild the stack completely.

A simple smoke test will determine whether there is an issue with your flues. This you can do yourself in conjunction with your neighbour.

After that you may need to employ a chimney company who can rod the flue, carry out a CCTV camera survey of the lining, report to you on the extent of damage to the flue and estimate the cost of repair. The first task in repairing the chimney is to clean the chimney flue itself. This will reduce the mess of soot and dust, and more importantly allow you to see the full extent of the damage.

If your flue lining is damaged you will have to decide on a suitable remedy and depending on the extent of repair required you may have to a) open up the chimney breast in sections from within the dwelling and replace damaged flue liners or b) insert a metal flue lining to the inside of the flue from above.

Unfortunately, we don’t have a Party Wall Act here, and we rely on common law rather than legislation to settle matters such as this. So it is cheaper to negotiate and agree works with your neighbour rather than bring something like this to court.

Pat McGovern is a member of the Building Surveying Professional Group of the Society of Chartered Surveyors Ireland. scsi.ie

QI have an issue with my attic when the temperature plummets. I upgraded the loft installation two years ago and since then have noticed water droplet build-up on the felt. I have installed ventilation tiles into the roof but the issue still persists. The last solution suggested to me was that I should change the felt on the roof, which would mean removing the tiles. Have you ever heard of this?

A You refer to changing the roofing felt, which I assume at present is a bituminous, impervious felt. Breathable membranes are used today but replacing the felt is a costly solution, which involves removing and reinstating roof tiles and battens.

The membrane does allow movement of water vapour through it and some manufacturers even claim that these do not need ventilation. However, these membranes have not been tried and tested over any significant period.

A ceiling covered with insulation will act as a barrier to prevent heat loss. This should be continuous but is often breached by gaps such as at access hatches, recessed lights, penetrating services and ducting extracting air from showers into the attic.

When the warm air meets the colder roofing felt it will condense and form water droplets. Bituminous felt significantly reduces the air movement and consequently reduces the amount of evaporation in the roof space. Cross flow of air is essential and in modern homes this is usually provided by preformed, perforated slots in the eaves. I have noted large gaps between these vents during inspection of some dwellings, where they should equal not less than a 10mm continuous air gap for a typical pitched roof.

You have recognised the problems and installed tile vents, which need to be closely spaced. There are proprietary ridge vent tiles but these are rarely used.

Ensure the insulation is free from the eaves. Check the amount and spacing of the soffit vents. Gables allow the opportunity to add vents. There are proprietary continuous ventilators that are placed under the front row of slates. A roofer will need to remove and refit the lower four courses. Preformed vent slots can also be placed between the insulation and felt at eaves. Check insulation is evenly distributed and placed over and not below the water tanks.

Improving the ventilation and ensuring it is evenly distributed should deal with your problem and is more cost-effective than installing a breathable membrane. A healthy roof void needs a draughty void. The type and construction may even have a bearing on the problem. If the problem persists it may be worthwhile consulting a local chartered building surveyor.

Jim Drew is a member of the Western Region Branch of the Society of Chartered Surveyors Ireland. scsi.ie

QWe are considering extending our home considerably and have recently received planning permission. With the introduction of the Home Renovation Incentive this is probably the best time to have this work carried out. Do I need to purchase public liability and employer liability insurance when having builders carry out this work?

AWhen a client engages with a contractor and enters into contracts, it is essential that they take advice in connection with the builders’ employer liability insurance/ public liability insurance and contractors all risk insurance. You need to ensure the cover is adequate and also current.

The first step is to contact a broker and consult with them on the matter. Once they are able to confirm the cover is adequate and current, and all other matters with regard to price and abilities are satisfactory, the contract with the builders may be drafted and completed.

Once this has occurred and the builder has taken possession of the property, the cover for employer liability insurance/ public liability insurance is the builder’s responsibility.

I would advise you to maintain your domestic policy cover over the duration of the work but an additional cover should not be required once your contractor demonstrates adequate employer liability insurance/ public liability insurance and contractors all risk insurance.

You may find it useful to consult the Society of Chartered Surveyors Ireland Home Renovation Incentive Guide (available at scsi.ie) if you have further queries, as this will inform you about what you need to know when you are organising to have construction work done on your home and would like to avail of the tax credit provided in Budget 2014.

Liam Murphy is a member of the Project Management Committee of the Society of Chartered Surveyors Ireland. scsi.ie

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