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Memberships and Licences Posted 3rd March 2013

Memberships And Licences In Roofing

What does it mean if a tradesman is a member of a trade association? Or they have a licence for their trade?

From the outside looking in it can appear to make this person seem more legitimate than a tradesman that is not but is this really the case? With membership of a trade association it does pay to discover exactly what this will mean to you the end user as the membership in many cases is really only there for the tradesman and does not really offer anything extra to the end user that you would get with a tradesman who is not a member of a trade association. The trade association needs paid subscriptions to operate and it is not really in their interests to cancel memberships and lose subscription monies. I would be really interested in the actual figures regarding this and I would imagine cancelled memberships are a really low figure. This could of course indicate a really high skill level of the membership but in my experience this is not the case. If you are choosing a tradesman because they are a member of an association your decision making could be flawed and you could well be not getting the best man for your job.

I personally think a recommendation from a trusted friend or colleague is of a lot more value than memberships etc.

Licences in theory are a good but the real reason for the licence is to sign off the work as carried out/supervised by a qualified licence holder and you may well not get the licence holder who signs for the work actually doing any work on your job at all. This is of course only relevant to building consent based work and no licence is required for non-consent based work. I know many excellent tradesmen who are not members of any association and do not have a licence so please be careful basing your decisions on the fact that they are a member of an association or have a licence because for non-consent based work you can use who you want to do the work.

For the record I hold licences for my trade but do not have a membership of any association.

Author - ST

Installing Lead Flashing is a skill Posted 16th February 2013


I have recently seen a number of new lead flashing installations that have been really quite bad and it is disappointing to see. Because Lead as a Flashing material does have no equals, it will last lifetime and needs no maintenance if installed correctly. However in the wrong hands it can be costly disaster that may make you seek cheaper alternatives in the future.

It should become quickly apparent if your chosen Lead Flashing installer is capable of doing the job. Do they have the correct tools and equipment? Do they use silicone or mastics to provide the seal on corners or details? (this is wrong if you are in any doubt!!) The Lead flashing should be welded or bossed into the required shape and if they cant do that they are not a capable installer and you should seek out a tradesmen who can.

Author - ST

Do Not Re-coat Concrete Tile Roofs - It Is A Waste Of Money.Posted 9th February 2013

Paint A Roof?

This keeps coming up and even though I have mentioned this before it does show that it needs dealing with again. Painting concrete tile roofs does not extend the life of the tile it is purely cosmetic and if you are being told differently you are quite simply being lied to.Painting metal roofs does make sense as these rely on the paint for protection and this does need maintenance and periodic re-coating.

Concrete tiles come out of the factory with a 50 year guarantee and this has been the case for many years so if you have a house that is over 50 years old with concrete tiles (it should be noted that some of the older tiles are more robust than others) you may be looking at replacement sooner rather than later and painting it will not do anything other than change the colour.

If you do decide to have your concrete tile roof re-coated make sure you do check afterwards as I have come across many newly painted roofs that have a number of tiles broken during the re-coating and not been replaced but stuck together with a mastic and then painted over. In this case the mastic will fail and then no amount of magic paint will solve this problem.

I strongly advise doing an independent search regarding re-coating of concrete tile roofs and I am sure the information will back up what I am saying.

Author - ST

Can You Batten A Roof Correctly?Posted 19th January 2013

Batten A Roof

If the roof material is tiles or a sized slate are the exposed faces uniform in appearance or worst of all up and down showing a complete lack of technical skills and if this is the case maybe it would be better to get a professional tradesmen to do the work next time.

When a roof is battened you have the first batten which will have a minor adjustment available to use and the top batten which in most cases will be as high up the roof to give as much cover as possible on the ridgeline. A tradesman who is skilled will measure the roof before any battens are nailed and calculate the battening measurements needed to make the finished appearance uniform and as if a professional tradesman has done the work. This will involve use of the chosen roof material to gauge a minimum and maximum measurement that can be used and then working this into the measurements gained from measuring the roof.

With a roof with a continuous fascia line that is consistent in measurement this should be an easy task however if the roof has steps In it to different sections or is not consistent in measurement it may become more complicated and test the skill level of the tradesman. In an ideal world any steps in the roof will have been clearly thought out and will correspond to fit in with the ideal spacing of the chosen roof material but this needs an architect who really does know everything about the building they are designing and will have accounted for everything with the measurements put in place. But as we all know this does not happen very often and it is then up to the tradesman to try to accommodate these steps and if possible have the consistent spacing work even with the steps.

When this situation arises I do actually love the challenge of making this work and more often than not this goes completely unnoticed because you have made the transition between different roof faces that good. It is times like these that it normally is only you that can congratulate yourself on a job well done! But you may be lucky and another tradesman or whoever with an eye for this sort of detail may notice and then compliment you on your obvious skill level.

Maybe this is why tradesman who do take pride in their work do examine other peoples work and sometimes wonder why they actually call themselves �fully qualified� or �time served�.

To me you are either a good at what you do or simply aspiring to be as good as the tradesman that are.

Author - ST

Clay Roofing Tiles.Posted 8th January 2013

Clay Roof Tiles

Clay roofing tiles are today mass produced but originally they were individually hand-made. And even though they do tend to have the same manufacturer�s warranty as concrete roofing tiles they do seem to have a longer lifespan and you can in many cases safely re-use them but simply add a new underlay and batten.

Clay roofing tiles seem to be predominately from Europe with France and Italy being recognised producers of quality Clay roof tiles. They have been produced there for many centuries and with this you do get methods that produce consistent results for the tile in shape and colour.

This has always been my main problem with Clay tiles as you do seem to get a number of bad tiles that will simply not fit with the others. Again a good roofer would remove these but there are also many bad roofers who would probably not even notice and or even bother to rectify this problem.

As is the way of the world today we are now getting clay tiles from all corners of the globe which does make things more complicated for the roofing contractor to know the good from the bad. Because of the access we all now have to information and products it is quite easy to find seemingly ideal solutions to save money by buying products directly and getting a contractor to install labour only. But with this option you may be going by a picture or a few choice selections sent as samples which may not truly reflect the actual bulk load that arrives. Although they do not have the multitude of colours available that concrete tiles do the ones that are available do always seem to have a �warm� glow when you look at them. There are some manufacturer�s who can add more colours to the range but how this impedes on the price I do not know.

Side by side with concrete tiles you will pay about 50% more for the supply and install of the clay tile. Mainly down to the fact you have less concrete tiles per square meter than clay roofing tiles and the clay tiles themselves are also more expensive. In summary the clay tile will last longer and involve less maintenance but will cost more to install. As a roofer I do like the look the clay tile roof gives. I give them a thumbs up!

Author - ST

Which Concrete Interlocking Roof Tile Profile Gives Better Performance?Posted 29th December 2012

Concrete Tile Performance

You have two basic profiles with concrete roof tiles the double barrel or flat, the double barrel has many variations in the dimensions in setup but the principle remains the same whereas the flat is well basically flat! Although there maybe concrete tiles available that do not interlock these are not common place so in general terms if you are using a concrete tile it will be of the interlocking variety. These tiles have on the underside a water channel which tends to be a weak point in certain profiles of tile.

Over many years of roofing I have come to the conclusion that the double barrel tile is the better choice for the least problems as it seems to be able to withstand the wear and tear better than its flatter counterpart.

I have seen many newly installed flat tile roofs with numerous missing corners on the bottom water channel which obviously have not been replaced due to not been seen or not bothering to replace. I personally do a complete check of any roof I have finished and if there is an issue like this I will replace the broken tile, the customer is paying for a new roof and not a new roof with breakages that need repairing.

Are these breakages the fault of the roofer who installed the roof? I would say no as this tile does seem to have a weakness in this area as the problem appears too often in this particular area for it to be an installation problem every time. I do think as probably many other roofers do that with the flat profile concrete tile you have to make a special point of looking for this issue when you have completed your installation and then correcting � this assumes that you care about the finished appearance of the completed work.

The double barrel tile because of its shape must avoid this issue as you will not have all your weight on the tile across the full surface and as is the case with any roof it is never perfectly level. With this use of wood for the rafters and tile battens small discrepancies will be there because of shrinkage and allowable tolerance levels for cutting sizes. This has a roll on effect with the flat tiles if the roof is uneven and foot traffic over the roof you will get breakages but these do seem to be less with the double tile.

If it is choice between the two I would always advise not using the flat profile.

Author - ST

Pre-Holed Slates Could Be Bad For Slate Roofing.Posted 22nd December 2012

Pre-holed Slates

This maybe a small thing that could be overlooked by many roofers but have you considered the difference between pre-holed slates and those that are holed on site?

Pre-holed slates seem to be predominately sized slate (all the same length and width) which seems now to be the slate of choice because cost wise it works out cheaper compared to the supply and fix of a random slate (different lengths and widths) roof. My main problem with pre-holed slate is that it is drilled (this is just a hole in the slate) and with this you do not get the countersunk hole on the slate whereas if you hole slate on site you use a holing machine which gives you a countersunk hole (a countersunk hole will taper giving you a fixing limit and also a secure fix). And because slate is a surface fixed material how this is nailed has implications over the longer term for the slate.

With a countersunk hole you can't nail the slate too far whereas with a drilled hole you can nail the slate too far which will stress the slate and bring the probability that it will not last the true lifetime of the material. You can also not nail the slate far enough which will result in the slate rattling in high winds again due to bad installation rather than material failure. Again this will not happen with the countersunk hole with the slate holding in the correct position after nailing.

I would be interested to hear why slates when holed are now drilled because to me this does show a lack of understanding on the part of the supplier of good installation methods as drilling in a hole in the slate does not give you a suitable fixing point for this type of material. I do genuinely think the only reason is money based because it is obviously faster. However it should be noted that the quality end of the market i.e. Burlington does not supply slate pre-holed and the slate is holed by the Slate Roofing contractor. Although the cost will be more I think this is the correct method as the hole will be then countersunk and many of the issues coming from pre-holed slate will be avoided.

This is an issue I do think should be looked at as we are seeing more and more slate roofs failing with slates splitting and cracking due to incorrect installation rather than just inferior materials.

Author - ST

Know Your Roofing Contractor.Posted 16th December 2012

Roofing Contractors

One thing which is not often considered when hiring a roofing contractor is what supplier the contractor uses for the roofing material, this could be slate, metal, concrete/clay tile, shingles etc.

Most contractors will have suppliers they regularly use and in hiring that contractor you are essentially also using their chosen suppliers. This has good and bad implications, on the good side the contractor will have probably decided on this supplier because their products give them the quality and price that they consider best reflects there ethos and you will have no doubt decided on this contractor because you have also done your homework and decided on what you want from the contractor. But on the bad side you could also be committing to a product that although your contractor considers being right it may also bring with it many issues you also as the end user should consider.

Here are some questions you should consider asking or looking into:-

    1. Is this a new product and the contractor has been offered a good rate to use it and your home is now effectively an active trial and with any new product it could quite easily fail and the supplier with it.

    2. Is there a possibility there may be further additions in future years and then a need for more of this product? This may not be a bad thing but does your contractor hold exclusive rights to supply of this product and leaving you really with only them as an option because sometimes you may wish to change to a different contractor for various reasons (this is a whole other area of discussion which I will deal with at a later date).

    3. Could there be future supply issues? Even consider over-ordering the quantities required as although many contractors will leave extra material behind if future repairs are required some will not so you then have to contact them and again you may not wish to! Obviously this is not really relevant to metal sheets as they will rust if not stored correctly.

    4. To further expand on the previous point if the products imported then you should really consider ordering extra as supply does become an issue if you have to import from another country.

In summary when you choose your roofing contractor you will decide what you want from them be it quality, price or speed. Hopefully you can get all three but whoever you hire remember to do your homework on the product they will use and its supply.

Author - ST

Slate, Concrete/Clay Tiles or metal?Posted 8th December 2012

Slate, Concrete or Metal?

If you had a choice of any roof material what would you choose? This assumes money is not a barrier and all the materials are readily available. What does each material offer? Let's take a look at them.

Slate and Clay tile are the natural material out of the options however this may limit colour choices whereas concrete tiles do have a wider colour choice and metal does have a massive range of colours to choose from. Concrete tiles are as their name suggests cement based, while metal has different components depending on the grade you want but are most definitely not a natural resource. If time is an issue metal is the quickest to install followed by the concrete/clay tiles and then Slate but does this give an indication to what to expect lifespan wise from your chosen material?

I would say yes as I do not know of a material deemed of higher quality that you can install faster than a material of a lesser quality and if this statement was true I would expect the lower quality and longer to install material to very quickly become obsolete. As longer install time does mean a higher cost. From an aesthetic point of view Slate does look like a 'picture postcard' compared to the other materials when completed. However Metal can create many wonderful shapes and no doubt give Architects dreams of 'awards' with its clean lines and modern look. But I have always believed it is the customer who should have the final say on what their house should look like (assuming they are not constrained by local building laws) and too many times Architects impose their will on the customer and steer them away from their preferred choice for not the right reasons. I would advise anyone considering their different options with roof materials to do a bit of digging around as there is information out there and you can then make an educated decision that will suit you.

Maintenance wise the metal does need more looking after than the other options with Slate being the least in need of upkeep. And I would even go as far to say that a Slate Roof would if correctly installed with quality materials be maintenance free. Whereas a metal roof will need maintenance and in comparison to a Slate Roof it would be unfair to compare life expectancy as even when a Slate Roof does need renewal you can in many cases re-use the slate and just need to re-new the roof underlay and battens this is also true for Clay tile roofs and to a lesser extent Concrete tile roofs. Whereas this would not be possible with a metal as this will need replacing many times in comparison to the Slate/Concrete or Clay tile roofs.

What would you put on your roof given a choice of these three materials?

Author - ST

To Paint Or Not To Paint A Concrete Tile Roof?Posted 27th November 2012

Painting Concrete Roofs

A brief overview of a concrete roof tile will as its name implies be a cement based product which means it is man-made with a colour added to the surface to give different options. Different manufacturers will have different methods to get to this end process but you are looking at normally a 50 year product warranty for it.

The main reason I have felt the need to write something regarding this particular roof material is because of the practice of roof painting which I can assure you is not a cheap option for what you are actually paying for. I should also clarify I mean the painting of concrete tile roofs and not metal which obviously will need this sort of maintenance because of the nature of the material.

I have heard of many so called reasons why you should need to give these type of roofs this life extending treatment but I can honestly say when you look at them they don�t really make much sense. The only reason you should paint a concrete tile roof is for cosmetic reasons because all of the other reasons that will be bombed at you are utter garbage.

How do I know this you ask? I don�t need to go into any long diatribes with this � ask the �tradesman� who is telling you that your roof needs this treatment this question:-

Do you paint the whole roof tile? And the answer could well be � Of course we do, we wash the roof then we seal the tile and then give it a top coat. They may even give the tile 10 coats of paint it does not really matter.

You asked them do they paint the whole tile � they don�t. I have yet to see them remove the tiles from the roof and paint the whole tile and this would obviously include the water channel that is on the underside where the two tiles join.

See no amazing facts to give you, just plain common sense. If you claim the roof needs painting you surely need to paint all exposed areas and I imagine water channels are I would guess exposed...

Author - ST

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