Building a porch / mud room

[hhb]

We're considering adding a porch / mud room to the front entry of our MH, probably 8' x 10'. This would be on deck blocks or similar, set up on posts, very simple, but insulated. Going to use standard 2" x 6" construction, fibreglass insulation, exterior sheathed in OSB, then tar paper and cedar shingles. Roof would be shed style with no peak following the roof line of the MH, shingled. I'll wire it for a heater and lights, inside will be vapour barrier & drywall, nothing fancy here. I think these are pretty common. Any idea of cost to build something like this?

The other question is attaching it to the MH. Our MH is up on blocks, as would this porch, so I understand attaching them solidly together could lead to problems because of frost heaves. One idea I had was to attach some kind of rubber "gasket" between them, but actually not connect the porch to the MH other than the rubber. This would keep drafts and stuff out but allow a little movement. The roof of the porch would tuck under the MH roof and continue the same roof line (it's a pitched, shingled roof).The MH movers showed me some rubber they use for the bottom of skirting that is about 3" to 4" wide, fairly thick like maybe 1/4" or better. I was thinking something like this although I have no idea what to buy for that. Other idea was to simply build it with a small gap between the MH and porch frame, and fill the gap with expanding foam - but that might grab too much I thought. Any other ideas on what to use to connect a porch to a MH?

[Greg]

Unless BOTH the home and porch (mud room) are set up on below the frost line footers you will have problems sealing the two. Frost heave will push the two apart at different rates and usually different directions.

Greg

[homebuff]

Greeting's Mark & hhb!
I built a 12x16 ft. porch a long time ago onto my 16x60 mh.
The only problems I had were keeping the joint's between the mh & porch from leaking when it rained real hard.
The water leaked down in between the wall & almost caught my home on fire.
It sure put a damper on thing's when I had to remove the trlr. side panel's to repair the wiring shorted by the water.
I finally got that fixed by applying 6" width Aluminum sticky tape across the length of the porch & trlr. roof joint.
I already had flashing across it though.
I made the mistake of screwing the upper 2x6 runner to the trlr with long lag bolt's.
I've been told by Mark & Greg that's not a good idea.
It keeps the porch from flxing like it need's to.
I have mine on one half sitting on the concrete patio & the other half on flat concrete blocks on the ground.
Good thing is it's still standing wit no warpage or leaning.
I was considering some day completely inclosing the whole thing & make it into a additional room.
Good luck on your's hbb!
You & Mark have a great weekend!
David