Roofing/shingles gaps



Our roofer just finished combination shingles and flat roof ( IB system). Please see some pictures of the gaps and holes that were left in the shingle where they meet the chimneys or the blocks.  I asked about this and he said it's ok as there are layers underneath.    Also, the edge of the shingles that come in contact ( not overlapping) with the flat IB system part of the roof, are not attached in a way that I can't lift a row.  I can lift the row of shingles about 3 or 4 inches , just the edge.  Is this ok?  

We did have the old roof entirely removed.  What do you think?  

Thank you,   Gabe

You mentioned all the shingles were removed.
The shingles when they meet an adjacent masonry (brick)wall, siding (metal, plastic, wood), dormer or chimney are flashed in with step flashings. Small pieces of L-shaped metal that is installed for every row of shingles. This metal overlaps so the water running down the roof runs over this metal like a sloped eaves trough.

So if your roofer has installed them at the chimney, how has he finished the roof so the water will not get behind them? Your photo shows a masonry (brick chimney) but I do not see any metal flashing up the chimney to the mortar joint (horizontal line in brick).

So when rain hits the chimney where does it go, under the shingles?

Sorry not impressed with this installation. Does the roofer know how to read (a shingle wrapper). Did the roofer give you his own warranty for installation (workmanship), normally stated from 5-10 years. If so, he will repair any leaks  due to installation for that time frame. If not good luck.

The flat IBI roof is a plastic vinyl roof that is probably terminated at least under three courses (rows) of shingles up the roof. He can not stick the shingles to the IBI because it is not compatible with asphalt plastic cement (mastic or bull).

again any warranty from the roofer on this flat roof? If so great, if not good luck.

Hope this helps to some degree. If not feel free to contact me again.

Check photos on web and punch in chimney flashings to see what I mean.  


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D. John Henderson


My 33 years in the building science business has involved air barriers, waterproofing, and flat & steep slope roofing systems.


My roofing encompasses commercial systems (BUR, mod-bit, single-ply) and residential applications (asphalt shingles, cedar shingles, slate and metal. I am cognizant of code stipulations in regards to FM and UL for commercial roofs.

Attended numerous courses offerd by Roof Consultants Institute, Roofing Industry Educational Institute, Factory Mutual Research Corporation, University of Wisconsin, and BURSI. Lectured for RCI and mentored at a local university for a Building Science Certificate.

Past/Present Clients
Government, commercial businesses such as The GAP, hospitals, school boards as a roof designer.

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