Solar Analysis, Via Germanico - Bolzano

VIA GERMANICO 148, RIONE PRATI, ROME 

1. MODELLING THE BUILDING

Before starting the solar analysis let’s add some details to the facade in order to have a more accurate model.

First of all let’s start with the windows

Make sure to set the plane on the surface you want, then start drawing with the “line” tool or “rectangle”.  To make it faster draw one window and then copy it with the right pace on the whole surface.

Once you got this you can start modelling your solid by „subtracting“ the rectangles you’ve been drawing.

Select the shape  and then click on : create form > void from

Now you’ve got an orange parallelepid , set the right measure, make sure it‘ s negative (add  - ) so that the void would automatically go backwards and make a hole in your volume.

Unfortunately you can’t select all the rectangles at once, so you have to repeat the procedure for all the windows and doors, otherwise the create form tool won’t work.

In this case we thought it would be more accurate to add also the small terrace at the first floor and add all the details, as its railing is quite massive and creates a shadow almost as if it was a whole solid.

Also we couldn’t leave out the trees which are an important feature for all the Rione Prati, not only for the quality they give to the urban space but also for the impact they have on the environment around them.

On Via Germanico the trees are quite tall and they make a nice shadow in summer on the street and the buildings.

We’ve created some very simple masses using a circle for the log and some concentric splines for the crown. 

2. SOLAR ANALYSIS

Now we’re ready to start the solar analysis, this tool will tell us the amount of heat per hour on the surface we’re studying, it is measured as kWh/.

Of course this kind of information should influence the project in two phases, first of all by deciding the disposition of windows, terraces, patios or open spaces in general , and then in a second phase to decide the shadowing tools, the types of windows and glasses, the stratigraphy of the walls and so on.

You may have to activate the solar radiation button by downloading some patches for Vasari and installing them, they can easily be found on the internet.

Now click on Analyse > Solar Radiation

Then you’ll have to select the mass to analyse, once you´re done click on the cursor icon.

You can set the accuracy of the analysis and the units you prefer, it should be better to start with low resolution and then try again with higher precision otherwise it may take a lot for the program to process everything. 

You can also select the style to display your data, it could be with colours or also numerical

Click on Style and create a new one

CONSIDERATIONS

We analysed the East and South façade, of course it´s clear that the second one is more affected by the solar radiation as in summer it is directly invested by the sun almost all day long. We can see though that even the little projection of the roof casts a shadow on the top of the building, it is clear that when the sun is high, with this exposure it takes only a little horizontal screen to avoid direct radiation.

Anyway, as it is an old historic building it wouldn`t be possible to think to change its features in such an invasive way, actually the current solution should guarantee a certain comfort within the building, having the shutters just outside the window so that the glass doesn`t heat too much. Also being a building with a continuous structure with massive walls helps to keep the indoors fresh.

We can see that the presence of the trees doesn´t affect too much the building in summer, as the sun is very high and the shadows don´t always reach the façade.  On the other hand in spring they naturally screen the lower part of the building even at midday. 

Here is the global analysis of the facades, we've changed the settings to "multiday > one year study":

Here we can see the global radiation (we´ ve chosen the "multiday solar study" on the solar analysis settings) and we confirm that the southern facade has higher values of exposure and we can see how the presence of the trees changes the impact on the lower part of the building

It  is interesting to see how a small terrace can change the values on the façade, here we can see two pictures showing the solar analysis for the summer solstice at 12 pm, that goes to show that to avoid sun exposure in summer even a small horizontal screen can really make the difference. In this particular case the door below is the entrance to the building, so there isn't any particular benefit as it would be for the shops next to it.

It is interesting how the different exposure affects some aspects of the building, here we can see how the humidity problem on the east side does not involve the southern façade. Anyway the general good maintenance of the plaster on the whole building hides these kind of differences and we couldn't find many anomalies.

BOLZANO, ASLAGO PROJECT AREA

In Bolzano we have a completely different situation, here the solar analysis is influenced by the presence of a mountain very close to our area, on the east side.

This means that it takes a while after the sunrise to have a complete illumination of the site, especially in winter.

We can see by the solar analysis that the hillside and the slope are clearly colder, but still a certain amount of sunlight seem to reach the project site, as we can see in the pictures below showing the solar analysis set on multiday > one year study .

We think that the main goal of our project is not only to reach the standards requested for the building performances, but to try to think at public open space that can be enjoyable all day long also in winter. It can only be done by studying accurately the sun path and shadowing on the area and all the environmental features of the site.