Hello All!
Just renewed my subscription after 20+ years away so I apologize in advance if my posts are not in the correct forums. I made the mistake of removing some loose siding to try and repair it and opened up the proverbial 55 gallon can of worms. Sheathing was rotten, deck (16’X40′) was about 1/4″ from falling out of the joist hangers, deck framing was rotten, etc, etc. The 2×2 siding turned into new windows, doors, siding, decking, etc. at the worst time in recent history for lumber prices. Doing as much as I can for some sweat equity and also it’s almost impossible to get a competent contractor who is not booked 6 months to 1 year out. So I have repaired all the deck framing and was wondering if the pro’s here could give me some direction or point me to relevant articles. I am a mechanical contractor by trade and have renovated several houses, but at 53 I have finally learned that some times you don’t know what you don’t know. So here are some basics of what I have now.
32’X50′ ranch, 5 pitch roof w/2X8 conventional framing 16O/C. Deck is L shaped and 16’X~38′ on back of house, wraps around the side to another 8’X20′ section of deck. The house is on a hill so rear deck is ~ 9′ above grade.
I repaired the deck and replaced some key footings. I made the beam of 5 2X12 pt beams with junctions all centered on posts below. The posts are 8X8 PT. I want to add a gable dormer so I replaced the existing 10″ footings with 36″ bigfoots and 12″ sonotubes where the posts will support the deck and proposed roof, and used 28″ bigfoots and 12″ sonotubes for the remainder of the footings. All footings are 5-6′ deep( My lot is primarily sand and I wanted as much footprint as possible to avoid settling so I went overboard) Tried hiring three different architects to design some of the deck roof details and everyone was too busy to take on another project.
So here are my questions.
1-Can anyone provide any info on adding a large gable dormer. I have posts 3′ out from the house where the 2 beams/top plates would extend out from the house. Then there are 2 more posts that would carry the “outside” end of the top plates and transfer the weight to the beam below the deck. These posts are located directly above the posts that support the beam for the deck. So the top plates would extend out from the house ~ 16′ and each will be supported at two points by 8X8 posts, 1 3′ out from the house, and another ~ 13′ out from the house. The top plates will cantilever over the outer posts ~ 2-3′. I would like to keep the rafters the same pitch as the house. I contacted Weyerhauser to design the top plates and IIRC they came up with 2 11 1/4″X 1 7/8″ paralams screwed together for each top plate. I have added 4 2X6’s to the wall of the house where the top plates would meet the house to provide an additional load path to the foundation.
So my question is-would I just set my post height so the the top plates for the new dormer will sit on-top of the top plate of the wall of the house? Or would it be acceptable to lag a piece of dimensional lumber to the existing wall and then attach the new top plates to that? I think there will be very little weight transferred to the house due to the post 3′ out but not 100% sure.
2-I want to have a paver patio below the 16X37 area. I was looking at Trex Rainescape but for the price I could get stainless steel sheet and make troughs in between the joists for less. Your thoughts either way?
3-I want to use premium decking, and my current material of choice is Ipe. I have a french door with low-E glass that faces directly south. I have concerns about the reflected heat causing damage to a composite material. I was looking at Trex, Wolf, and Azek and spoke with reps from all companies who had similar responses across the board. All said this was a concern and that should any issues occur this is not a covered issue under the waranty (understandable). What are your experiences in this situation and do you agree Ipe would be best for my application or are there alternatives I have not listed? If Ipe is best, should I avoid 6″ boards due to higher potential for cupping, or is that not a concern?
4-Sorry, I skipped a question on the gable dormer over the deck. The dormer will extend out ~16′ from the house and the total width will be ~ 19′. I will use a ridge beam that could be self supporting but will not be required to. I want to have a barrel ceiling but will still probably have a few collar ties. I am trying to match the pitch of the house so will probably stick with 5 pitch. Question is given my existing roof (5 pitch w/2X8 @ 16 OC) is it necessary to pull the roof decking to double some of the rafters? Considering that I believe in over-engineering to avoid issues in the future I would normally just do this but considering the ridiculous price of lumber I would like to avoid doing this if possible. (Due to the framing of some internal structures in the house it would be very difficult if not impossible to do this from inside.
Again, if I have broken any rules please advise and I will repost in the appropriate forum. Or if there are relevant articles please point me toward them. I looked for several hours over the course of a few days using multiple search terms and was not able to find any reference material that answered my specific questions. I truly respect the volume of skill on this site and appreciate any input (Productive or otherwise!) Thanks in advance for any help you can offer. Just trying to do the best job possible.
P.S. See some basic drawings I have attached if they helpful in your response.
Replies
There is a lot here.
Yup. Any thoughts?
Are you suggesting I break it down to separate items? Happy to do so if it helps. LMK. Thanks for the response.
Just right off the bat, I agree about the Rainscape, use 5 V crimp with the crimps up and screw it to battens.
Ipe would be my next to the last choice of decking. It's heavy as lead, very hard to fasten down so it looks good, and turns silver-gray after exposure to the sun. Use a decent synthetic decking like Trex or Azek. It will look almost the same when you're 73.
Thanks for the reply. I have installed ductwork most of my career but have always used a shop for anything other than basic field fab, cutting ducts, etc. However I don't know what a 5V crimp is. I was planning on a 90 degree bend on each side, fastening to the joist, then using either HDPE or butyl tape wrapped over the top of the joist and down into each trough. I want the dry space under the deck but I also never ever want to touch it again. The deck was only about 9 years old but the PHO used steel roofing below the joists to provide a dry area. However he left no way to clean out the debris that inevitably migrates onto below deck systems. I believe this debris (ALOT! of wet leaves etc) caused the deck to suffer an early death. When I pulled it apart 1/2 of the joists broke into 3 or 4 pieces when I dropped them. I want to build a deck that will still be there when I'm 93! Or at least until after someone else owns the house. Regarding your comments on the decking, do you feel I will be OK using composite (PVC wrapped) decking with a large low-e south facing door? The manufacturers feel it is a cause for concern. The upper tier TimberTech was my first choice until I learned about the possible impact from low E glass. Don't know how much of a concern this is in my region (New England) or if it's only a concern in sun states like Florida or Arizona. Thank you very much for your response. Stay safe.
5V is more commonly known as barn roofing.
I've seen Low E windows melt vinyl siding here in FL but haven't seen any deck damage. That doesn't mean it can't happen, just outside my experience range.
That was what was under the deck framing before I took the deck apart. I think that was what contributed to the old framing rotting out so soon. The roofing was installed pitched away from the house on what would be "inverted sleepers. The debris that migrated down there piled up and stayed wet as the PHO never left a way to clean it out. I never thought about ripping the roofing into strips and installing between the bays. That is a great idea and the major reason I rejoined the site. Thank you so much for the response!
Are you suggesting I break it down to separate items? Happy to do so if it helps. LMK. Thanks for the response.
I was thinking about the structure of the roof. Do you just like the look of collar ties?
And it seems like you have a lot of flexible dimensions.
Remember that you will have a roof over the whole thing.
We have a similar setup, with a covered screen porch over a walk-out basement. stays dry enough to keep firewood, but it does get wet in a windy storm.
Uncle Mike,
Thanks for the reply. Not married to the collar ties. With a self supporting ridge and the way Weyerhauser engineered the beams that will carry the roof, I am not sure they are necessary, but again I am always trying to overengineer somewhat. I am hoping to have a barrel type ceiling look under the gable roof when done. Collar ties were additional just to aid in preventing the top plates from spreading.
With a roof over the deck, I would not want places handy inside for birds to nest.
Since you can have a cleaner support, I would skip the collar ties. (my preference)
Did you get a design for a beam to support the outside of the dormer (and the ridge beam), or will you need that center post?