sun>ice

arch595mt - mass timber design, fall 2021
san marcos, tx
prof. paul fast

context

this sustainable ice arena in san marcos, texas leverages timber to create a warm environment in juxtaposition with the coolness of the ice. situated at the intersection of civic and recreational areas, texas state university, and spring lake, the ice arena bridges between all three areas, amplifying the surrounding community.

in order to fit in better with the low rise buildings nearby, the exterior of the ice arena is simplified. an asymmetrical gabled roof, oriented so the largest side faces south, encloses a more complex interior structure. the orientation of the building and the roof design intentionally create space for an efficient solar panel system. to achieve a low profile exterior and dynamic interior, the structure uses a two-part roof/ceiling. the roof is connected to a curved ceiling by interstitial members. this truss-like system has a number of advantages. these include easy hvac access, spatial interest, and opportunities for panelized exterior cladding.

structure

three bar building

why?

centers the ice rink
simplifies column grids
concentrates programmatic elements

how?

four column lines

two layer roof/ceiling

why?

allows freedom in sculpting interior space
cavity is ideal for large HVAC loads
potential for panelized roof to place photovoltaics

how?

one unifying volume

why?

makes the interior a surprise
area is mostly low-rises with flat roofs, so a lower profile exterior would be appropriate here

how?

relatively simple roof profile

design sketches

design section

geometry

materials

because the two layers are independent in terms of form, the roof can easily be rationalized and clad. here, cladding consists of a 3-ply clt roof sheathing underneath either solar panels (on the south side) or accoya panels (on the north side), a treated material suitable for exterior applications. the ceiling side doesn’t need to be clad, freeing it up to be a more expressive, curved shape.

members

this curved beam is too long to be transported on one flatbed truck, so making it a gerber beam splits it into three pieces in an efficient way. gerber beams are essentially two cantilevered beams with a smaller beam dropped in the middle to connect them. this works extremely well with the three-bar building system in place. additionally, splitting the beam in this way simplifies the joints at the columns. moving the splice between beam portions rather than directly at the columns negates the need for a 4 member connection.

structural plans

final design

section

plans

hvac and electric loads are intended to be run through the cavity between the roof and the ceiling. because ice rinks necessitate a large hvac load, especially in texas, elevating the services above the ceiling will allow for a semi-exposed system. it will be high up and the girders and purlins on the ceiling will provide some separation from the programmatic elements for both aesthetic and acoustic purposes. additionally, hvac can be dropped independently for enclosed rooms because the roof/ceiling cavity gives the system freedom to be efficient.

lateral support is provided by masonry shear walls. these walls will transfer loads to the foundations. for the perimeter walls, the exterior face will be a warm brick. the interior face of the wall will be a wood veneer. this veneer will also be applied to both sides of the wall when shear walls are used in non-perimeter applications. while clt shear walls would also work from a structural point of view, to make the interior shine, the timber is concentrated on the interior. a brick exterior will make the entry into the ice arena more special because of the juxtaposition between the two materials.