Question: Worrying incompetance or just minor niggles in the last minute rush??

[mjanesuk]

Moggy,
The roofer did use 6mm screws, just not enough. Having spoken to him I get the impression that he was quite happy with just the one screw, and it had not been explained that this might not be sufficient.

I can see that the batterns may be the better way on my skimpy fink rafters but it would take time, which this firm were clearly not prepared to spend.

Part of the problem is that the Spark and the roofer seemed to be independant and came on different days. One saying its his job... and the other saying no its his...

I think I will have to put a long snagging list together and get a date when the roofer and the electrician are there on the same day. And see if they will do any of it.

If there is lots of work to do anyway, I may also suggest they move the lower sttring of 6 up against the upper string. There is a 350mm gap betwene the two rows of panels at the moment, which seems a bit odd. I think it was purely because the roofer put the lower rails on the roof 1st to be able to stand on them to reach the upper ones. It was not a very comprehensive plan - a rought doodle on the back of a piece of paper - basically 10 portrait at top, 6 landscape at bottom, here are the panels and off you go boys.

 

[moggy1968]

yes, but by using 6mm fixings he is still breaching building regs unless he battens the rafters.
personally I wouldn't have either of them back, they're clearly not up to the job. why get a bodger to fix a bodge?
The job has been priced to be complted correctly and to conform to building regs, Part P, MIS, DTI etcetc. The fact it takes a long time to get it to comply is no excuse, shoot the surveyor!!
I do a rough doodle on a bit of cardboard box before I start and it's always accurate, again no excuse, however, if I don't have adjustable roof brackets I do often leave a gap of about 6 inches between upper and lower rows as that disguises any irregularities in the roof shape so the panels look level, even if they aren't quite

 

[mjanesuk]

OK, Yes I see what you mean with the batterns.

Frankly the surveyor was more of a salesman and didnt appear to know much about what he was fitting. In fact I think he mentioned that he had never been on an installation.

 

[moggy1968]

that does rather beg the question why did you use them?!!

 

[SolarCity]

if I don't have adjustable roof brackets I do often leave a gap of about 6 inches between upper and lower rows as that disguises any irregularities in the roof shape so the panels look level, even if they aren't quite

That's a really good idea. We use adjustable on most of our installs but they were hard to get hold of in the rush we have just had - We had a right game getting some of the panels to sit right on some sites.

 

[moggy1968]

yeh it was a move forced on us for the same reason but it actuallly looks really tidy and much quicker than faffing about trying to get adjustable brackets lined up

 

[SolarCity]

Your biggest issue, as far as I'm concerned, is the one-screw-fixing problem. I find it absolutely astounding. Using an impact driver means that it is easier to screw the fixing in - it makes absolutely zero difference to how strong the fixing is.

I know it irritates some members when I talk like this but the crew that fitted your install are grossly incompetent and utterly out of their depth. I suspect there are more issues with your install that you aren't even aware of.

 

[SolarCity]

To be fair, it only takes me half hour or so to adjust the variable brackets to suit. I just level out the lower rail and then use my adjustable level to get the other rails to suit. Of course, some roofs have so much variation in them that you cannot help.

 

[moggy1968]

got to agree. you need to get someone that knows what they are doing to come in and do an assessment and provide a cost to put right which you can then put to the company.
we used to use a spare rail laid accross to level them up which was pretty quick (after having panels on and off in the early days!) but I think now if the roof looked basically flat we would always use non adjustable and leave a small gap between the rows

 

[mjanesuk]

Hmm. Well yes.

Basically I ran out of options with the local installers I had lined up just before the bombshell dropped. They were not big enough to carry stock or ba able to source new suppliers in time, so I had little option. I did check out all the acreditation details and phoned references, etc. but sometimes it just goes bad.

The roof is only 20 years old so it is pretty level. They did not use adjustable brackets, but it looks OK.

 

[mjanesuk]

Moggy/Biggs - thanks, have been out.

I seemed to be heading in this direction as well - getting someone in to look at the system. There is lost I think is wrong, but what I dont have is the experience to come up with realistic suggestions of how to fix/change/redesign what needs attention.

Given the fact that my efforts to check these guys out did not work last time (and I was being cautious) how do I make sure I get someone with the same pride in their trade as many of the posters on this site?

I live in Buckingham, if anyone has any suggestions.

I wil post some pics tomorrow. I know nothing is ever easy, but from what I have read over the past few months and seens a few other installs, mine should have been a piece of piddle (12m wide roof, 20 ys old good condition, S facing, no obstructions at all, open loft space, easy scaffold & access.....

I need to look into the issue of fixing dia and rafter width for building regs. - I did not entirely get it, but that makes it even worse if that is the case.

 

[mjanesuk]

I have just been reading through previous posts on fixings and now get the 4x screw dia min. edge distance.

I just saw reference to using noggins if the roof is trussed. This was in the context of doubling up structurally unsound rafters and maybe unloading the truss nodes.

My question is therefore should I be asking for noggins or 2x4's screwed either side fo the rafter truss. Or does it not matter in this case. My assumption is that batterns should not be problematic as long as they dont happen to coincide with a node.

 

[liquidity]

Your brackets are inadequately fixed!!

There is an issue with rafter/screw sizes. I believe building regs require that the screw diameter should be no more than 25% of 50% of the rafter width, 4.6mm in your case. The various solar regs require that the minimum screw size is 6mm. The way we get round skinny rafter is to batten either side of the rafter in the area of the fixing with 12 inch battens, effectively widening the rafter. we can always get the 2 fixing screws into even a skinny rafter by careful placement of the bracket and slight angling of the screws. I use 6mm screws from screwfix with a hex shaped head rather than the 8mm ones Krannich supply as these are way too destructive on this rafter thickness.
Of course doing all this takes time.

Why is an electrician working on solar who doesn't like heights and isn't insured to work at height!!!

Any place I can find the regs online about bracket spacing, screw sizes, etc?

 

[moggy1968]

bracket spacing depends on your windlift calculations from the BRE guide.
screw sizes I forget but it's either the DTI guide or MIS which conflicts with the guide in the building regulations

 

[liquidity]

Hmmm.... my installer used 1 bracket per rafter across the entire width of the rails. The rafters are spaced at 400mm and are 35mm wide. I believe he used 2 5mm screws per bracket. The brackets look to be Schucos as per Schuco - Roof anchor - pantile 10.1/2 - Segen No extra blocks of wood were added to "widen" the rafters. Location is West Sussex in a reasonably level suburban area about 5 miles from the coast. Should I be worried? They're all still there after Thursday's storm!