PHILADELPHIA | W Hotel & Element by Westin | 617 FT | 51 FLOORS

[1487]

Originally Posted by City Wide

a poured in place, concrete core, with the usual slip form construction, seems to always move upward well ahead of the rest of the construction, regardless of what type that is.
If in comparing apples to apples in different construction methods for the structural elements, one can use the point in time when a floor is ready for the trades to start working on other components, such as HVAC, wiring, fire safety, glazing, etc. and from what I've heard and observed is that steel with poured in place floors, is faster.
But it doesn't ever seem like its that simple; there are so many different factors to consider, the type of curtain wall might very well effect the type of floor system used. I always thought that the choices in construction methods would have been documented by now and one could just pull a book off the shelf and be told which path to follow. But from what I hear that's not at all the case. The trouble is that there doesn't seem to be any neatly fixed answers as to why and when to build one way and when to build another way, and what the pluses and minuses are.

material costs, building design and site conditions all make a difference.

[thisisforreal]

Nov 10th:

[thisisforreal]

Yesterday's shot was rotated too far counter clockwise and that's going to drive me nuts.

Nov 11th:


Folks, that's a hotel lobby about to be poured. We're almost at Floor 0 for you European lurkers.

[rduffy5]

Thisisforreal,

Thank you so much for these photos. It's really so cool to get this vantage point and get it nearly every day. You're the bomb.

[thisisforreal]

Nov 11th:


Nov 14th:

[Philly Fan]

^ Street level deck being poured! That's some kind of milestone, isn't it?

[RWSMADCONC]

Originally Posted by Philly Fan

Apparently, steel framing is more cost-efficient for buildings with higher ceilings, such as those found in office buildings, while poured concrete is more cost-efficient for residential buildings and their lower ceiling heights.

CIRA Walnut/FMC is an example of a building with both office and residential uses---steel frame was selected for the office floors because it allowed for clear spans of around 45 feet or so from the core to the exterior without columns, and allowed enough space above the ceilings for integration of the MEP systems--floor to floor is 14 ft 4 in, ceilings are around 10 feet, nice column-free space!!! The residential component, from level 28 to Level 46 are 10 ft 8 in floor-to floor with a 8-1/2 to 11 inch slab; in the major living spaces and especially at the exterior rooms, the slab soffit is exposed as the ceiling for some nice tall ceilings--more than 9 feet. The interior spaces over the kitchen and bath areas is a dropped drywall also to allow horizontal MEP. The 28th level is a transfer floor, and a row of columns is introduced there for the residential component but they hide in the bathroom and kitchen walls---so steel framing can give long column-free spans but is deeper and lighter than concrete would be--and concrete works well for relatively shorter spans but can be shallower in those spans, and the soffit can be the ceiling. So it is a concrete building on top of a steel building with a concrete core throughout. The top of the concrete portion is at elevation 688 ft. 6 in, a little higher than W will be......

[looper121]

This thing looks a lot different from a year ago, but man is it moving slow.

http://forum.skyscraperpage.com/showthread.php?t=201482&page=60

[summersm343]

^^Projects always move extremely slow in the ground when there is underground parking. Once it gets out of the ground, this thing will shoot up.

[Philly Fan]

Originally Posted by RWSMADCONC

CIRA Walnut/FMC is an example of a building with both office and residential uses---steel frame was selected for the office floors because it allowed for clear spans of around 45 feet or so from the core to the exterior without columns, and allowed enough space above the ceilings for integration of the MEP systems--floor to floor is 14 ft 4 in, ceilings are around 10 feet, nice column-free space!!! The residential component, from level 28 to Level 46 are 10 ft 8 in floor-to floor with a 8-1/2 to 11 inch slab; in the major living spaces and especially at the exterior rooms, the slab soffit is exposed as the ceiling for some nice tall ceilings--more than 9 feet. The interior spaces over the kitchen and bath areas is a dropped drywall also to allow horizontal MEP. The 28th level is a transfer floor, and a row of columns is introduced there for the residential component but they hide in the bathroom and kitchen walls---so steel framing can give long column-free spans but is deeper and lighter than concrete would be--and concrete works well for relatively shorter spans but can be shallower in those spans, and the soffit can be the ceiling. So it is a concrete building on top of a steel building with a concrete core throughout. The top of the concrete portion is at elevation 688 ft. 6 in, a little higher than W will be......

Thanks for the detailed explanation! Just a quick follow-up question: why couldn't steel also be used for the residential portion, using walls, ceilings, and soffits for vertical and horizontal MEP runs, while also allowing more flexibility for layout variety and alterations in present use or future adaptive reuse (such as conversion from hotel to rental or condo or even office use, etc.). In other words, especially with the extended period required for construction of the transfer floor, it seems that steel would have provided advantages and flexibility without any disadvantages. So what am I missing?

[RWSMADCONC]

Originally Posted by Philly Fan

Thanks for the detailed explanation! Just a quick follow-up question: why couldn't steel also be used for the residential portion, using walls, ceilings, and soffits for vertical and horizontal MEP runs, while also allowing more flexibility for layout variety and alterations in present use or future adaptive reuse (such as conversion from hotel to rental or condo or even office use, etc.). In other words, especially with the extended period required for construction of the transfer floor, it seems that steel would have provided advantages and flexibility without any disadvantages. So what am I missing?

Concrete is inherently fireproof; steel would require application of some product (not necessarily aesthetically appealing) or enclosure in a fire-rated assembly (costly) or a combination of the two, which adds depth. A concrete flat plate can economically achieve spans at a depth perhaps 60% of a steel framing grid (columns, beams and girders) ---in the DC-Metro area, where there are significant height restrictions, concrete is used because the shallower depth can mean the difference between a building having say, 6 or 7 stories. This also holds true for residential uses also unless the walls are bearing walls up to a point--an example of a steel-joist-bearing wall can be seen in the townhomes at 1601 Vine, where the slab and steel joists are pretty thin, only a little deeper than a concrete slab would have been, but do require a rated ceiling. However, should a user subsequently desire to "blow out that wall!!" like they do all the time on "Property Brothers" or "Flip or Flop" they might be shit out of luck (the wall is carrying the load) where in a concrete frame building, the columns do the work and the walls are truly partitions....is that what is meant by flexibility???
The ultimate answer is economics--a concrete frame may be more costly but it saves on fireproofing and some ceiling costs, can be shorter floor to floor thus reducing the amount of exterior wall cost, or possible allowing for more gross square footage to amortize total building costs over, and may be faster to erect than steel---and interest on a construction loan can be huge so shaving two months or more off the end to end schedule can make a difference.

[Philly Fan]

Originally Posted by RWSMADCONC

Concrete is inherently fireproof; steel would require application of some product (not necessarily aesthetically appealing) or enclosure in a fire-rated assembly (costly) or a combination of the two, which adds depth. A concrete flat plate can economically achieve spans at a depth perhaps 60% of a steel framing grid (columns, beams and girders) ---in the DC-Metro area, where there are significant height restrictions, concrete is used because the shallower depth can mean the difference between a building having say, 6 or 7 stories. This also holds true for residential uses also unless the walls are bearing walls up to a point--an example of a steel-joist-bearing wall can be seen in the townhomes at 1601 Vine, where the slab and steel joists are pretty thin, only a little deeper than a concrete slab would have been, but do require a rated ceiling. However, should a user subsequently desire to "blow out that wall!!" like they do all the time on "Property Brothers" or "Flip or Flop" they might be shit out of luck (the wall is carrying the load) where in a concrete frame building, the columns do the work and the walls are truly partitions....is that what is meant by flexibility???
The ultimate answer is economics--a concrete frame may be more costly but it saves on fireproofing and some ceiling costs, can be shorter floor to floor thus reducing the amount of exterior wall cost, or possible allowing for more gross square footage to amortize total building costs over, and may be faster to erect than steel---and interest on a construction loan can be huge so shaving two months or more off the end to end schedule can make a difference.

Thanks again! I think you've answered more than a few folks' questions here.

[thisisforreal]

Nov 14th:


Nov 15th:

[MikeNigh]

this is above ground now.

[thisisforreal]

You can't see it from my pictures, but the rebar in the SW corner is about 12-15ft above grade at this point.

Nov 17th:

[Whu215]

Originally Posted by MikeNigh

this is above ground now.

The deck that was just poured is almost level with the sidewalk now.

[City Wide]

somebody---hint hint mr. owner---should throw a 'out of the hole party', with dancing and burgers from Wendy's (fresh, never frozen)

I'm too lazy to check the back photos, but which took longer, digging the hole, or getting out of the hole?

[Whu215]

Originally Posted by City Wide

somebody---hint hint mr. owner---should throw a 'out of the hole party', with dancing and burgers from Wendy's (fresh, never frozen)

I'm too lazy to check the back photos, but which took longer, digging the hole, or getting out of the hole?

Not sure on that, I got on the job July 22nd.

Also, that party would most likely be at the Gold Club😳😂

[Philly Fan]

Originally Posted by Whu215

Also, that party would most likely be at the Gold Club😳😂

What time should we meet you there?

[Baconboy007]

Originally Posted by Whu215

Not sure on that, I got on the job July 22nd.

Also, that party would most likely be at the Gold Club😳😂

Out of the hole party seems like a perfect themed party for the gold club.