detect presence of vcredist - using the UpgradeCode

in a wix burn bootstrapper bundle: how to detect whether ms vcredist 2013 x86 is present or not?
i'm doing a check for the Upgrade Id / UpgradeCode of that particular package, but the bundle always installs it afresh, even though it is installed already.

...
<Bundle>
    ...
    <Chain>
        <!-- redist packages -->
        <PackageGroupRef Id="redist"/>
        ...
    </Chain>
</Bundle>

<Fragment>
    <PackageGroup Id="redist">
        <PackageGroupRef Id="redist_vc120" />
        ...
    </PackageGroup>
</Fragment>

<Fragment>
    <!-- vcredist 2013 x86 -->
    <?define vcredist2013minversion="12.0.21005"?>
    <Upgrade Id="B59F5BF1-67C8-3802-8E59-2CE551A39FC5">
        <UpgradeVersion Minimum="$(var.vcredist2013minversion)" Property="VCREDIST2013INSTALLED" OnlyDetect="yes" IncludeMinimum="yes" />
    </Upgrade>

    <PackageGroup Id="redist_vc120">
        <ExePackage Id="vc120" Cache="yes" PerMachine="yes" Permanent="yes" Vital="yes" Compressed="yes"
            Name="redist\VC120_Runtime\vcredist_x86.exe"
            InstallCommand="/quiet /norestart"
            InstallCondition="Not VCREDIST2013INSTALLED"
        />
    </PackageGroup>
</Fragment>
...

is there anything wrong with the InstallCondition?
or do i need to add a DetectCondition?

in the log file it reads:

Detected related package: {13A4EE12-23EA-3371-91EE-EFB36DDFFF3E}, scope: PerMachine, version: 12.0.21005.0, language: 0 operation: MajorUpgrade
Detected package: vc120, state: Absent, cached: None
Condition 'Not VCREDIST2013INSTALLED' evaluates to true.
Planned package: vc120, state: Absent, default requested: Present, ba requested: Present, execute: Install, rollback: None, cache: Yes, uncache: No, dependency: None
Applying execute package: vc120, action: Install, path: <path and command line>...
Applied execute package: vc120, result: 0x0, restart: None

but also removing the InstallCondition and replacing it with the following DetectCondition did not work:

<PackageGroup Id="redist_vc120">
    <ExePackage Id="vc120" Cache="yes" PerMachine="yes" Permanent="yes" Vital="yes" Compressed="yes"
        Name="redist\VC120_Runtime\vcredist_x86.exe"
        InstallCommand="/quiet /norestart"
        DetectCondition="VCREDIST2013INSTALLED"
    />
</PackageGroup>

--

edit:
just to explain further: i'm trying the approach with UpgradeCode because i don't want to check for a particular installation package but for a minimum version.