Ask Your Question

Angie's List Answers is the trusted spot to ask home improvement and health questions and get answers from service companies, health providers and consumers. For ratings and reviews on companies in your area, search Angie's List.

Top 30 Days Experts
Rank Leader Points*
1 kstreett 240
2 Guest_9020487 110
3 Guest_9190926 105
4 GoldenKid 100
5 ahowell 95
6 KnowledgeBase 95
7 skbloom 80
8 Guest_98024861 70
9 Guest_9311297 70
10 Guest_9400529 70

*Updates every 4 hours

Browse Projects By Category

Question DetailsAsked on 10/15/2014

How much to expand rear dormer half bath to full bath on Long Island ?

Do you have the same question? Follow this Question

Voted Best Answer

Assuming you mean widening it along the length of the roof rather than out into the attic space, probably about 3-5 times what you think it should cost, because you are talking a potentially major structural modification to the roof framing to transfer the load of the rafters you will be taking out to widen the dormer, especially if the bathroom will be more than about 5-1/2 wide (which typically takes out 2 rafters total). Can be a lot simpler if you have load-bearing walls along a hallway under the center of the attic than if there is no intermediate support in the attic between the walls.

In addition to the cost of the upgrade to full bath - probably at least $5000 and up to ten times that much if you get carried away (typical or representative cost info in the Home > Remodeling, Kitchen and Bath link in Browse projects at lower left), you can get an idea of the dormer cost by checking out the prior similar questions about building/widening dormers by putting the word dodrmer into the Ask box and about 5 similar questions will pop up - a few additional similar ones will appear as links below those answers when they come up.

Really though, since so much depends on your house construction and how big this dormer is going and which way the bathroom is oriented relative to the house, and since you will need an architect or structural engineer (architect probably, due to electrical and ventilation and plumbing as well as structural mods) to do plans for bidding and to be ableto get a building permit, you should start with selecting an architect and come up with a conceptual plan, with a preliminary cost estimate. Then you can decide if you want to go ahead with the project or if it is out of range.

Also bear in mind, if your rafters are architecturally concealed (not in an open attic space) then in that area that architectural covering/ceiling will likely be significantly diturbed, because commonly the rafters adjacent to the walls of the dormer have to be doubled up at least on the dormer side, and sometimes on both sides of the roof, so it might mean taking out about an 8-10' wide section of ceiling across the attic to do this, then replacing/refinishing that. Not a terrible cost but adds to the bill and disturbance.

Answered 5 years ago by LCD

Related Questions

Terms Of Use
Privacy Policy