I did a roof today. New Sh mixed at about a 4% it looked ok when I was there but I just drove by it hours later and it looks bad. Lots of brown and yellowish brown streaks. I’ll try and get pictures I’m assuming it’s dead organics but it looks bad. It’s hard without pictures I know but Is this something I should let the rain handle or should I go and re treat and rinse
I just drove by and took some pictures it’s getting dark out so the pictures aren’t the best. It looks better then it did when it was sunny out. The roof looks untreated but it shot it twice with 4% maybe even a little over. The picture the streaks look black but during the day when it was light out it was definitely brown.
Well if its bown and yellowish is it dead moss and or lichen? Or was the roof really bad with dark black algae and now its lighter but still not very even? Did you hit the roof twice?
You nees to hit that again its not clean. You should easily be able to see those spots like that when your there cleaning still. How are you applying SH to get your 4% you mentioned?
I sprayed that entire section twice the whole roof was covered. I agree from that picture it looks unclean but during day time when it was sunny it was more brown and yellow then black like the picture looks. I used my 12v batch mixed 4gallons Sh 12.5 mixed with 7 gallons water and 11oz of cling-on for 11 gallons total mix
Unless my SH wasn’t fresh but I just got it from my supplier
Just looking at the size of the area you treated and the ammount you listed would have been only 11 gallons total. On a cloudy day even thats not enough mix to properly saturate that roof twice and with that much soap like you had and in the sun you must have just done a light dusting and it evaporated your mix. Go back and hit the whole thing again. Mix up 6 sh 6 water Go back and when you leave it should look 95% even maybe a few light shadows that the rain will rinse away.
Brian,
The front part doesn’t look too bad. Most of that will come down, but up towards the top needs to be hit again as well as some of the bottom shingles on both sides. You can’t not do those just because you get runoff over them. It’s too diluted by then. That backside, you definitely have some black you need to hit again.
I’m kind of disappointed you left it like that. You should have been able to see it from the ladder. I’d had black streaks I’ve had to hit 4-5 times. Some are just stubborn. Once you put a coat on it, take a break for about 10min and then look at roof to see if there are any spots that need to be hit again before you move ladder.
I always try to get a coat on the lower 3-4’ of roof first. It will kind of act as barrier for the runoff. You just need more practice.
I’d tell client there are a couple of places you’re not happy with, but that you want to wait for a good rain. 4% is plenty strong, but if it’s real bad you need to put decent amount of mix. Also, if it hot and dry and has been for several days, wet the roof down first, let it sit for about 5-10min, then put your mix on it. It will be softer and absorb more of the mix.
4 Likes
Thanks for your feedback. I do need more practice I’ve done a few roofs already all with good success. Not sure why this one gave me
Problems. Not to make excuses but the entire job from start to finish was issue after issue. Yesterday before I even posted on here I texted the customer and said exactly what you said. I’m not happy with a few spots I want to come back out and re treat the roof. I sent them two messages but haven’t heard back.
One thing I did notice was when I was spraying I could literally see steam coming the roof from my mix. I’m assuming this was due to a hot roof coming in contact with cool sh and water? I have never seen that before could that have contributed? Could the roof have been so hot it just evaporated before it had a chance to really work.
Maybe a little, not that unusual here in the south or anywhere it’s hot this time of year. another reason to pre-wet.
