Deck lean-to

[DHT]Osiris

Lifer
Dec 15, 2015
17,567
16,933
146
Need a sanity check for anyone who's done anything like this.

We have a small deck on the back of our house with two doors that exit the home onto it. We've had issues with these doors/framing rotting, and I suspect it's due to water splashing up off the deck onto the door/frame (it's very obviously covered in splashed water after rainstorms). I've corrected some issues we've had with the gutters leaking, but it hasn't fixed the problem. As such, I'm looking for more of a blunt-force solution to the problem; cover the deck entirely.

The deck itself covers a rather large area, but is only about 4" off the surrounding concrete, and made of some kind of boarding, it looks/feels like plastic but could just be some peculiar coating. Under it is 2x4's or 2x6's end-up. My notion was to build something akin to the following (sans the dog), placed directly on the deck, no anchoring:
1602609416816.png

I'd use 4x4's for the primary posts, probably 3 at the low point, two on the high point; the center of that back post would be where a door is. I could do four on the back for structural reasons if necessary. 2x4's for the roofing, maybe 1x2's for the cross-beam things that hold the plastic corrugated roof if I needed to keep the weight down. And of course, the plastic corrugated roof.

My plan was to build it so the peak of the plastic was just up underneath the gutters, so literally any water from either the gutters or rain would slough off the deck entirely, eliminating my concerns about the doors rotting.

My concerns:
We get decent winds, though most of them come from a direction that this would be protected from. Regardless, should I concern myself with that corrugated roof ripping straight out of the screws? Should I be using some girthy washers to hold it in place, or reconsider the mounting situation?
I suspect with that much bracing it'd be fine with snow weight right?
If I place the whole thing directly on the deck, and place it in a way so the 4x4's are on a section of the deck which has a 2x4 on-end underneath, do you think it'll hold the weight + snow without cracking the deck board? These hold the weight of people, deck chairs, and everything else under the sun and I haven't had to worry about them yet. I'd much rather not tear the deck apart/start cutting boards to facilitate putting the 4x4's through to whatever's underneath.

Please feel free to critique/call me an idiot for considering this as an option, or give me a simpler/cheaper option for fixing my door rot problems.
 

herm0016

Diamond Member
Feb 26, 2005
8,524
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the screws will hold the panels down, that's how they are designed. you would need 2x4 for the cross pieces, and i would use 2x6 for the perimeter with the bracing just like is shown in the picture. 1x2 is not for something structural. you will need to attach it to the deck, otherwise it will fly into your house, or your neighbors house and cause real damage. The posts should not be more than 6 or 8 feet apart. I used that plastic for the temperature controlled windows on my greenhouse and it is holding up very well.



replace the door frames and keep them painted not an option? some door frames have plastic tails now as well.
 

[DHT]Osiris

Lifer
Dec 15, 2015
17,567
16,933
146
the screws will hold the panels down, that's how they are designed. you would need 2x4 for the cross pieces, and i would use 2x6 for the perimeter with the bracing just like is shown in the picture. 1x2 is not for something structural. you will need to attach it to the deck, otherwise it will fly into your house, or your neighbors house and cause real damage. The posts should not be more than 6 or 8 feet apart. I used that plastic for the temperature controlled windows on my greenhouse and it is holding up very well.



replace the door frames and keep them painted not an option? some door frames have plastic tails now as well.
The issues we've had with the door frames and doors are long-standing, and I can't seem to find anyone that can fix it properly. We got the most expensive crew in the area (who we actually trust, we've used them for tons of other jobs) to fully replace the doors and door frames, and less than a year later they're wicking moisture and cracking/rotting apart.
Hinge side of doorframe, inside of house:
1602613886153.png

Inside of doorframe itself:
1602613942455.png
End of door itself:
1602613981098.png

As a note, we're going to be getting the company to fix this, but apparently this is another situation where I need to learn everything there is about doors, doorframes, and hydrodynamics so that I can be sure that someone I've given a small fortune to will do it right.
 

[DHT]Osiris

Lifer
Dec 15, 2015
17,567
16,933
146
You will need to attach it to the deck, otherwise it will fly into your house, or your neighbors house and cause real damage.
Forgot this part... so regardless of the weight of the wood structure, you'd say it's just asking for it to turn into a sail regardless? I can probably mount it to the 2x4's under the deck, was hoping to avoid that though.
 

herm0016

Diamond Member
Feb 26, 2005
8,524
1,132
126
my grandfather started the pre-hung door industry back in the 50s? or so.

I think the water could coming in around the brickmould or the siding is not properly flashed along the side. is there head flashing above the frame and behind the brickmould? i will assume with these issues that you have 1 ft overhangs, I will never buy a house with anything less than 2 feet. is the deck sloped towards the house? is the bottom of the sill not properly sealed? what kind of siding do you have? there are so many little details the can make this fail. none of them are difficult or complicated, but some people just don't bother.

either that, or you live facing the ocean and have constant wind and rain towards that door.

yes, it will fly away if not securely bolted to the ground. My greenhouse is a steel pipe frame attached to a wood 2x6 "foundation" that is ballasted with 24000 lbs of rock. it moved around a lot until I put in spiral ground anchors with steel cables under tension tied to the roof system. it is extra windy here though.

ex, i have a small handyman business on the side. last week i installed ducting for a range hood out the side of a house. properly flashed, J channel around the vent with the corners bent to overlap like shingles, caulked on the back. etc... took 4 hours. too long they say!

whoever installed the patio door put a length of metal drip edge to hide the edge of the siding so that they did not have to unzip and reinstall the siding around the door, probably saved them 2 hours of work.. no J channel. it looks ok, but what they fail to understand is that the water coming down the siding just flows right behind the metal, to the top of the door, which may or may not be caulked ( and caulk is not a valid weatherproofing strategy) then if flows right down the side along the ragged edge of siding under the metal cover and into the edge of the sheathing on the house, or the door frame. but a vinyl slider wont rot, so who cares if the house falls down around it. the J channel provides a gutter around the door to catch the water and direct it down the sides to exit out the bottom without touching the door frame or structure.
 
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[DHT]Osiris

Lifer
Dec 15, 2015
17,567
16,933
146
my grandfather started the pre-hung door industry back in the 50s? or so.

I think the water could coming in around the brickmould or the siding is not properly flashed along the side. is there head flashing above the frame and behind the brickmould? i will assume with these issues that you have 1 ft overhangs, I will never buy a house with anything less than 2 feet. is the deck sloped towards the house? is the bottom of the sill not properly sealed? what kind of siding do you have? there are so many little details the can make this fail. none of them are difficult or complicated, but some people just don't bother.

either that, or you live facing the ocean and have constant wind and rain towards that door.

yes, it will fly away if not securely bolted to the ground. My greenhouse is a steel pipe frame attached to a wood 2x6 "foundation" that is ballasted with 24000 lbs of rock. it moved around a lot until I put in spiral ground anchors with steel cables under tension tied to the roof system. it is extra windy here though.

ex, i have a small handyman business on the side. last week i installed ducting for a range hood out the side of a house. properly flashed, J channel around the vent with the corners bent to overlap like shingles, caulked on the back. etc... took 4 hours. too long they say!

whoever installed the patio door put a length of metal drip edge to hide the edge of the siding so that they did not have to unzip and reinstall the siding around the door, probably saved them 2 hours of work.. no J channel. it looks ok, but what they fail to understand is that the water coming down the siding just flows right behind the metal, to the top of the door, which may or may not be caulked ( and caulk is not a valid weatherproofing strategy) then if flows right down the side along the ragged edge of siding under the metal cover and into the edge of the sheathing on the house, or the door frame. but a vinyl slider wont rot, so who cares if the house falls down around it. the J channel provides a gutter around the door to catch the water and direct it down the sides to exit out the bottom without touching the door frame or structure.
I understood ~70% of that, IT by trade, wishing I didn't have to learn so much about doors.
Here's a few additional pics (left side's the hinge side):
1602617540152.png
1602617572326.png
1602617589955.png
Signs of rust on the gutter are from poor sealant, I've fixed that for the most part, still getting some drips which I'm trying to manage still. It's ~1' overhangs plus whatever for the gutters.
 

herm0016

Diamond Member
Feb 26, 2005
8,524
1,132
126
fixing that gutter will be 80 to 90% of your solution.

take the board off the top, and see if their is flashing behind it. should only be 3 or 4 nails holding it in to the frame.

the door frame looks like its pushed towards the outside to make casing the outside easy.

see diagrams.

the casing/brick mould also helps secure the door when properly installed. nailed to the frame and the house. in your install it looks like it it just hanging out there. in the 2nd diagram they may or may not have flashed behind the casing and there could be a path for water to come in between the door frame and the stud. usually this is open or full of spray foam or stuffed with some fiberglass insulation inbetween the shims that the door frame is attached through. wont know till you take off some casing.
 

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[DHT]Osiris

Lifer
Dec 15, 2015
17,567
16,933
146
fixing that gutter will be 80 to 90% of your solution.
Yeah I thought so, I know the splashes from the gutter are a problem, just irritating how much. I'll try to prioritize that part.

take the board off the top, and see if their is flashing behind it. should only be 3 or 4 nails holding it in to the frame.

the door frame looks like its pushed towards the outside to make casing the outside easy.
We had issues with the boards surrounding the doorframes not being installed correctly on another set of doors done by the same crew, probably causing issues. Company will fix that I'm sure (every new crew says 'aw man, the last crew was terrible! then fixes stuff')

the casing/brick mould also helps secure the door when properly installed. nailed to the frame and the house. in your install it looks like it it just hanging out there. in the 2nd diagram they may or may not have flashed behind the casing and there could be a path for water to come in between the door frame and the stud. usually this is open or full of spray foam or stuffed with some fiberglass insulation inbetween the shims that the door frame is attached through. wont know till you take off some casing.
That makes sense. Here's an additional photo of the interior, to pair with the superb diagrams you sent.
1602623610566.png
Don't mind the lack of appropriate finish, I left it unfinished until I was sure this crap was all done with, apparently that was a good decision.
 

Greenman

Lifer
Oct 15, 1999
22,491
6,579
136
I understood ~70% of that, IT by trade, wishing I didn't have to learn so much about doors.
Here's a few additional pics (left side's the hinge side):
View attachment 31683
View attachment 31684
View attachment 31685
Signs of rust on the gutter are from poor sealant, I've fixed that for the most part, still getting some drips which I'm trying to manage still. It's ~1' overhangs plus whatever for the gutters.
That trim detail couldn't be worse. Any water running down the siding ends up behind the trim, and probably flows into the framing at the two jamb sides. It has to fail.

As far as the overhang goes, it has to be anchored down or the wind will pick it up and plant somewhere expensive. Without actual dimensions, I have no way of knowing if your joist sizing is correct.
 

[DHT]Osiris

Lifer
Dec 15, 2015
17,567
16,933
146
That trim detail couldn't be worse. Any water running down the siding ends up behind the trim, and probably flows into the framing at the two jamb sides. It has to fail.

As far as the overhang goes, it has to be anchored down or the wind will pick it up and plant somewhere expensive. Without actual dimensions, I have no way of knowing if your joist sizing is correct.
The trim was an issue on the french doors we also had replaced, another person came out after the fact and fixed that one, didn't fix the other though. Unsure why. I'll bring it up.

Probably just going to abandon the idea of the overhang for the moment, and focus on just getting the doors/gutters where they should be.