myBDAsites.com

I am thinking of having rectangular bay windows in our bedrooms.
Wondering if there is anything i should be concerned about? Can weather (sunny days and rainy days) have a play?
Are there any construction related things that usually get ignored?
Appreciate your input.

A lot depends on the design of the bay. Assume that you want a 2 feet deep window..

Need to have proper TMT metal structure work for both the lower and the upper part of the window.. this is a small work and usually the bar bending team is seen to not turn up.. (they prefer work like pillars or for roofing )

might require complex formwork. If let us say that your bay window is at 2nd floor, without having similar thing at the first, getting to reach that height of second floor can be very tricky ( standard form poles is 10 feet and managing 20 feet with that is quite difficult)

if the window shutters are at the end of the window, there is a high probability of water leaking through it as there is no rain shade to them. You will have to keep the windows always closed. Wooden windows will be more prone than aluminum or UPVC ones. Similarly, a higher exposure to sun.

If the windows are too big, there is a challenge with privacy, in case you are living in a busy area

very useful information ganeshncm.
Earlier I had decided to have 4" projection after the window shutters. Now I am thinking of changing that to 8" and reduce the depth of sitting area.

Don't reduce depth of sitting area else making bay window is useless. Also if you plan to fit UPVC windows check with window vendors in advance about the possibility of edges. and kind of profiles you will fit and choose shape of projection corner ( 90 deg or more artistic 120 deg etc)
frameless edge glass joint looks really need instead of pillars of wood /UPVC at the bay window corner.

Also if your roof slab is not laid make provision of baywindow as part of same slab it will.cost very little extra. You can avoid cantilever beams below window by using appropriate reinforcement.

Make sure that the shuttering and support poles before concrete pour is proper and earth on which pole is resting is well compacted and doesn't collect water.
Use steel poles and shuttering for projection as wooden logs and coconut fiber roap use to tie them slips/sags crating ugly overhang.

it.happned at my site we have 15.5 feet x 3 feet projection and this portion is 8 inch slab with double matting and 16mm / 20mm rods to avoid external cantilever beams.

It rained heavily on the dayof pour and when concrete pump poured M25 from RMC truck wooden shuttering pole went lower by may be by few inchs. There was no problem strenthwise but visually it was looking ugly.

fixed issue by cutting the 15x3 portion of slab with jackhammers and electric cutter but it was really tough task as slab was really very strong.

This portion was made again by using lockset to drill the old slab and inserting new rods and using Fosrock Nittobond to join old and new concrete while doing concrete pour for this area.

As a rule of thumb two chemicals both from Fosrock are very handy for extending slabs /RCC work. Thanks to my contractor who suggested and used them we have used at many places to extend projections to prevent water in window cill to roof size big windows.

1. Lockset ; drill holes at the side of slab and apply nittobond on the rods and insert them in older slab .
2. Nittobond : Chip and make old concrete edge rough paint with nittobond using brush. Pour new concrete in rest of area. The joint of old slab and new pour won't develop crack.

interesting ideas visualizer. extending the roof slab will make it easier. current plan is to ave a cantilever at 18" height from floor. This is going to be tied to a beam extending to two columns on each side.
roof is not done in my case. So it should be easier. will discuss with the contract and architect.

Pillers can be within the wall unless it is a poarch and if suppose you must have a cantilever, use inverted beams which will serve as window cill from sipport point of view there is no difference between beam below or above slab.

will keep that in mind.
i did notice your input on edges of window. uPVC vendors have option with glass only at the edges. However this is prone to seepage. I have also seen option with protective joint at the edges that will help avoid seepage. That is what i plan to use.